diff --git a/command.py b/command.py
index e8e32b4..725f0c8 100644
--- a/command.py
+++ b/command.py
@@ -1,6 +1,5 @@
 # coding=utf-8
 import logging
-import os.path
 import pymumble.pymumble_py3 as pymumble
 import re
 
@@ -10,15 +9,13 @@ import util
 import variables as var
 from librb import radiobrowser
 from database import SettingsDatabase, MusicDatabase
-from media.item import item_builders, item_loaders, item_id_generators, dict_to_item, dicts_to_items
+from media.item import item_id_generators, dict_to_item, dicts_to_items
 from media.cache import get_cached_wrapper_from_scrap, get_cached_wrapper_by_id, get_cached_wrappers_by_tags
-from media.file import FileItem
-from media.url_from_playlist import PlaylistURLItem, get_playlist_info
-from media.url import URLItem
-from media.radio import RadioItem
+from media.url_from_playlist import get_playlist_info
 
 log = logging.getLogger("bot")
 
+
 def register_all_commands(bot):
     bot.register_command(constants.commands('joinme'), cmd_joinme, no_partial_match=False, access_outside_channel=True)
     bot.register_command(constants.commands('user_ban'), cmd_user_ban, no_partial_match=True)
@@ -71,6 +68,7 @@ def register_all_commands(bot):
     bot.register_command('loop', cmd_loop_state, True)
     bot.register_command('item', cmd_item, True)
 
+
 def send_multi_lines(bot, lines, text, linebreak="<br />"):
     global log
 
@@ -79,19 +77,20 @@ def send_multi_lines(bot, lines, text, linebreak="<br />"):
     for newline in lines:
         msg += br
         br = linebreak
-        if (len(msg) + len(newline)) > (bot.mumble.get_max_message_length() - 4) != 0: # 4 == len("<br>")
+        if (len(msg) + len(newline)) > (bot.mumble.get_max_message_length() - 4) != 0:  # 4 == len("<br>")
             bot.send_msg(msg, text)
             msg = ""
         msg += newline
 
     bot.send_msg(msg, text)
 
+
 # ---------------- Variables -----------------
 
 song_shortlist = []
 
-# ---------------- Commands ------------------
 
+# ---------------- Commands ------------------
 
 def cmd_joinme(bot, user, text, command, parameter):
     global log
@@ -146,6 +145,7 @@ def cmd_url_ban(bot, user, text, command, parameter):
         bot.mumble.users[text.actor].send_text_message(constants.strings('not_admin'))
     return
 
+
 def cmd_url_ban_list(bot, user, text, command, parameter):
     if bot.is_admin(user):
         bot.mumble.users[text.actor].send_text_message(util.get_url_ban())
@@ -153,6 +153,7 @@ def cmd_url_ban_list(bot, user, text, command, parameter):
         bot.mumble.users[text.actor].send_text_message(constants.strings('not_admin'))
     return
 
+
 def cmd_url_unban(bot, user, text, command, parameter):
     global log
 
@@ -170,9 +171,11 @@ def cmd_play(bot, user, text, command, parameter):
     if len(var.playlist) > 0:
         if parameter:
             if parameter.isdigit() and 1 <= int(parameter) <= len(var.playlist):
-                var.playlist.point_to(int(parameter) - 1 - 1) # First "-1" transfer 12345 to 01234, second "-1"
-                                                            # point to the previous item. the loop will next to
-                                                            # the one you want
+                # First "-1" transfer 12345 to 01234, second "-1"
+                # point to the previous item. the loop will next to
+                # the one you want
+                var.playlist.point_to(int(parameter) - 1 - 1)
+
                 bot.interrupt()
             else:
                 bot.send_msg(constants.strings('invalid_index', index=parameter), text)
@@ -241,7 +244,7 @@ def cmd_play_file(bot, user, text, command, parameter, do_not_refresh_cache=Fals
         else:
             # try to do a partial match
             files = var.cache.files
-            matches = [ file for file in files if parameter.lower() in file.lower()]
+            matches = [file for file in files if parameter.lower() in file.lower()]
             if len(matches) == 1:
                 file = matches[0]
                 music_wrapper = get_cached_wrapper_by_id(bot, var.cache.file_id_lookup[file], user)
@@ -250,7 +253,7 @@ def cmd_play_file(bot, user, text, command, parameter, do_not_refresh_cache=Fals
                 bot.send_msg(constants.strings('file_added', item=music_wrapper.format_song_string()))
                 return
             elif len(matches) > 1:
-                msgs = [ constants.strings('multiple_matches') ]
+                msgs = [constants.strings('multiple_matches')]
                 song_shortlist = []
                 for index, match in enumerate(matches):
                     id = var.cache.file_id_lookup[match]
@@ -274,10 +277,9 @@ def cmd_play_file(bot, user, text, command, parameter, do_not_refresh_cache=Fals
 def cmd_play_file_match(bot, user, text, command, parameter, do_not_refresh_cache=False):
     global log
 
-    music_folder = var.music_folder
     if parameter:
         files = var.cache.files
-        msgs = [ constants.strings('multiple_file_added') + "<ul>"]
+        msgs = [constants.strings('multiple_file_added') + "<ul>"]
         count = 0
         try:
             music_wrappers = []
@@ -289,12 +291,12 @@ def cmd_play_file_match(bot, user, text, command, parameter, do_not_refresh_cach
                     music_wrappers.append(music_wrapper)
                     log.info("cmd: add to playlist: " + music_wrapper.format_debug_string())
                     msgs.append("<li><b>{}</b> ({})</li>".format(music_wrapper.item().title,
-                                                 file[:match.span()[0]]
-                                                 + "<b style='color:pink'>"
-                                                 + file[match.span()[0]: match.span()[1]]
-                                                 + "</b>"
-                                                 + file[match.span()[1]:]
-                                                 ))
+                                                                 file[:match.span()[0]]
+                                                                 + "<b style='color:pink'>"
+                                                                 + file[match.span()[0]: match.span()[1]]
+                                                                 + "</b>"
+                                                                 + file[match.span()[1]:]
+                                                                 ))
 
             if count != 0:
                 msgs.append("</ul>")
@@ -331,7 +333,6 @@ def cmd_play_url(bot, user, text, command, parameter):
         bot.send_msg(constants.strings('bad_parameter', command=command))
 
 
-
 def cmd_play_playlist(bot, user, text, command, parameter):
     global log
 
@@ -480,8 +481,10 @@ def cmd_rb_play(bot, user, text, command, parameter):
             msg += "No playable url found for this station, please try another station."
             bot.send_msg(msg, text)
 
+
 yt_last_result = []
-yt_last_page = 0 # TODO: if we keep adding global variables, we need to consider sealing all commands up into classes.
+yt_last_page = 0  # TODO: if we keep adding global variables, we need to consider sealing all commands up into classes.
+
 
 def cmd_yt_search(bot, user, text, command, parameter):
     global log, yt_last_result, yt_last_page, song_shortlist
@@ -516,6 +519,7 @@ def cmd_yt_search(bot, user, text, command, parameter):
     else:
         bot.send_msg(constants.strings('bad_parameter', command=command), text)
 
+
 def _yt_format_result(results, start, count):
     msg = '<table><tr><th width="10%">Index</th><th>Title</th><th width="20%">Uploader</th></tr>'
     for index, item in enumerate(results[start:start+count]):
@@ -602,7 +606,7 @@ def cmd_volume(bot, user, text, command, parameter):
     if parameter and parameter.isdigit() and 0 <= int(parameter) <= 100:
         bot.volume_set = float(float(parameter) / 100)
         bot.send_msg(constants.strings('change_volume',
-            volume=int(bot.volume_set * 100), user=bot.mumble.users[text.actor]['name']))
+                     volume=int(bot.volume_set * 100), user=bot.mumble.users[text.actor]['name']))
         var.db.set('bot', 'volume', str(bot.volume_set))
         log.info('cmd: volume set to %d' % (bot.volume_set * 100))
     else:
@@ -652,7 +656,7 @@ def cmd_ducking_volume(bot, user, text, command, parameter):
     if parameter and parameter.isdigit() and 0 <= int(parameter) <= 100:
         bot.ducking_volume = float(float(parameter) / 100)
         bot.send_msg(constants.strings('change_ducking_volume',
-            volume=int(bot.ducking_volume * 100), user=bot.mumble.users[text.actor]['name']), text)
+                     volume=int(bot.ducking_volume * 100), user=bot.mumble.users[text.actor]['name']), text)
         # var.db.set('bot', 'volume', str(bot.volume_set))
         var.db.set('bot', 'ducking_volume', str(bot.ducking_volume))
         log.info('cmd: volume on ducking set to %d' % (bot.ducking_volume * 100))
@@ -692,12 +696,10 @@ def cmd_remove(bot, user, text, command, parameter):
     global log
 
     # Allow to remove specific music into the queue with a number
-    if parameter and parameter.isdigit() and int(parameter) > 0 \
-            and int(parameter) <= len(var.playlist):
+    if parameter and parameter.isdigit() and 0 < int(parameter) <= len(var.playlist):
 
         index = int(parameter) - 1
 
-        removed = None
         if index == var.playlist.current_index:
             removed = var.playlist.remove(index)
 
@@ -707,7 +709,7 @@ def cmd_remove(bot, user, text, command, parameter):
                     var.playlist.current_index -= 1
                     # then the bot will move to next item
 
-            else: # if item deleted is the last item of the queue
+            else:  # if item deleted is the last item of the queue
                 var.playlist.current_index -= 1
                 if not bot.is_pause:
                     bot.interrupt()
@@ -715,7 +717,7 @@ def cmd_remove(bot, user, text, command, parameter):
             removed = var.playlist.remove(index)
 
         bot.send_msg(constants.strings('removing_item',
-            item=removed.format_short_string()), text)
+                                       item=removed.format_short_string()), text)
 
         log.info("cmd: delete from playlist: " + removed.format_debug_string())
     else:
@@ -726,7 +728,7 @@ def cmd_list_file(bot, user, text, command, parameter):
     global log
 
     files = var.cache.files
-    msgs = [ constants.strings("multiple_file_found") ]
+    msgs = [constants.strings("multiple_file_found")]
     try:
         count = 0
         for index, file in enumerate(files):
@@ -755,29 +757,30 @@ def cmd_queue(bot, user, text, command, parameter):
         msg = constants.strings('queue_empty')
         bot.send_msg(msg, text)
     else:
-        msgs = [ constants.strings('queue_contents')]
+        msgs = [constants.strings('queue_contents')]
         for i, music in enumerate(var.playlist):
-            newline = ''
             tags = ''
             if len(music.item().tags) > 0:
                 tags = "<sup>{}</sup>".format(", ".join(music.item().tags))
             if i == var.playlist.current_index:
                 newline = "<b style='color:orange'>{} ({}) {} </b> {}".format(i + 1, music.display_type(),
-                                                           music.format_short_string(), tags)
+                                                                              music.format_short_string(), tags)
             else:
                 newline = '<b>{}</b> ({}) {} {}'.format(i + 1, music.display_type(),
-                                                           music.format_short_string(), tags)
+                                                        music.format_short_string(), tags)
 
             msgs.append(newline)
 
         send_multi_lines(bot, msgs, text)
 
+
 def cmd_random(bot, user, text, command, parameter):
     global log
 
     bot.interrupt()
     var.playlist.randomize()
 
+
 def cmd_repeat(bot, user, text, command, parameter):
     global log
 
@@ -795,13 +798,14 @@ def cmd_repeat(bot, user, text, command, parameter):
 
     bot.send_msg(constants.strings("repeat", song=music.format_song_string(), n=str(repeat)), text)
 
+
 def cmd_mode(bot, user, text, command, parameter):
     global log
 
     if not parameter:
         bot.send_msg(constants.strings("current_mode", mode=var.playlist.mode), text)
         return
-    if not parameter in ["one-shot", "repeat", "random", "autoplay"]:
+    if parameter not in ["one-shot", "repeat", "random", "autoplay"]:
         bot.send_msg(constants.strings('unknown_mode', mode=parameter), text)
     else:
         var.db.set('playlist', 'playback_mode', parameter)
@@ -813,6 +817,7 @@ def cmd_mode(bot, user, text, command, parameter):
             bot.interrupt()
             bot.launch_music()
 
+
 def cmd_play_tags(bot, user, text, command, parameter):
     if not parameter:
         bot.send_msg(constants.strings('bad_parameter', command=command), text)
@@ -829,7 +834,6 @@ def cmd_play_tags(bot, user, text, command, parameter):
         log.info("cmd: add to playlist: " + music_wrapper.format_debug_string())
         msgs.append("<li><b>{}</b> (<i>{}</i>)</li>".format(music_wrapper.item().title, ", ".join(music_wrapper.item().tags)))
 
-
     if count != 0:
         msgs.append("</ul>")
         var.playlist.extend(music_wrappers)
@@ -842,8 +846,6 @@ def cmd_add_tag(bot, user, text, command, parameter):
     global log
 
     params = parameter.split()
-    index = ""
-    tags = []
     if len(params) == 2:
         index = params[0]
         tags = list(map(lambda t: t.strip(), params[1].split(",")))
@@ -880,8 +882,6 @@ def cmd_remove_tag(bot, user, text, command, parameter):
 
     params = parameter.split()
 
-    index = ""
-    tags = []
     if len(params) == 2:
         index = params[0]
         tags = list(map(lambda t: t.strip(), params[1].split(",")))
@@ -897,7 +897,7 @@ def cmd_remove_tag(bot, user, text, command, parameter):
             if tags[0] != "*":
                 var.playlist[int(index) - 1].remove_tags(tags)
                 log.info("cmd: remove tags %s from song %s" % (", ".join(tags),
-                                                          var.playlist[int(index) - 1].format_debug_string()))
+                                                               var.playlist[int(index) - 1].format_debug_string()))
                 bot.send_msg(constants.strings("removed_tags",
                                                tags=", ".join(tags),
                                                song=var.playlist[int(index) - 1].format_short_string()), text)
@@ -914,7 +914,7 @@ def cmd_remove_tag(bot, user, text, command, parameter):
                 for item in var.playlist:
                     item.remove_tags(tags)
                     log.info("cmd: remove tags %s from song %s" % (", ".join(tags),
-                                                              item.format_debug_string()))
+                                                                   item.format_debug_string()))
                 bot.send_msg(constants.strings("removed_tags_from_all", tags=", ".join(tags)), text)
                 return
             else:
@@ -926,6 +926,7 @@ def cmd_remove_tag(bot, user, text, command, parameter):
 
     bot.send_msg(constants.strings('bad_parameter', command=command), text)
 
+
 def cmd_find_tagged(bot, user, text, command, parameter):
     global song_shortlist
 
@@ -954,6 +955,7 @@ def cmd_find_tagged(bot, user, text, command, parameter):
     else:
         bot.send_msg(constants.strings("no_file"), text)
 
+
 def cmd_search_library(bot, user, text, command, parameter):
     global song_shortlist
     if not parameter:
@@ -993,9 +995,8 @@ def cmd_search_library(bot, user, text, command, parameter):
 
 def cmd_shortlist(bot, user, text, command, parameter):
     global song_shortlist, log
-    indexes = []
     try:
-        indexes = [ int(i) for i in parameter.split(" ") ]
+        indexes = [int(i) for i in parameter.split(" ")]
     except ValueError:
         bot.send_msg(constants.strings('bad_parameter', command=command), text)
         return
@@ -1033,9 +1034,8 @@ def cmd_shortlist(bot, user, text, command, parameter):
 
 def cmd_delete_from_library(bot, user, text, command, parameter):
     global song_shortlist, log
-    indexes = []
     try:
-        indexes = [ int(i) for i in parameter.split(" ") ]
+        indexes = [int(i) for i in parameter.split(" ")]
     except ValueError:
         bot.send_msg(constants.strings('bad_parameter', command=command), text)
         return
@@ -1049,7 +1049,7 @@ def cmd_delete_from_library(bot, user, text, command, parameter):
                 if 'id' in music_dict:
                     music_wrapper = get_cached_wrapper_by_id(bot, music_dict['id'], user)
                     log.info("cmd: remove from library: " + music_wrapper.format_debug_string())
-                    msgs.append("<li>[{}] <b>{}</b></li>".format(music_wrapper.item().type ,music_wrapper.item().title))
+                    msgs.append("<li>[{}] <b>{}</b></li>".format(music_wrapper.item().type, music_wrapper.item().title))
                     var.playlist.remove_by_id(music_dict['id'])
                     var.cache.free_and_delete(music_dict['id'])
                     count += 1
@@ -1078,6 +1078,7 @@ def cmd_delete_from_library(bot, user, text, command, parameter):
 
     bot.send_msg(constants.strings('bad_parameter', command=command), text)
 
+
 def cmd_drop_database(bot, user, text, command, parameter):
     global log
 
@@ -1091,6 +1092,7 @@ def cmd_drop_database(bot, user, text, command, parameter):
     else:
         bot.mumble.users[text.actor].send_text_message(constants.strings('not_admin'))
 
+
 def cmd_refresh_cache(bot, user, text, command, parameter):
     global log
     if bot.is_admin(user):
@@ -1100,13 +1102,16 @@ def cmd_refresh_cache(bot, user, text, command, parameter):
     else:
         bot.mumble.users[text.actor].send_text_message(constants.strings('not_admin'))
 
+
 # Just for debug use
 def cmd_real_time_rms(bot, user, text, command, parameter):
     bot._display_rms = not bot._display_rms
 
+
 def cmd_loop_state(bot, user, text, command, parameter):
     print(bot._loop_status)
 
+
 def cmd_item(bot, user, text, command, parameter):
     print(bot.wait_for_downloading)
     print(var.playlist.current_item().to_dict())
diff --git a/constants.py b/constants.py
index b4afd5d..355112d 100644
--- a/constants.py
+++ b/constants.py
@@ -1,32 +1,32 @@
 import variables as var
 
+
 def strings(option, *argv, **kwargs):
-    string = ""
     try:
         string = var.config.get("strings", option)
-    except KeyError as e:
-        raise KeyError("Missed strings in configuration file: '{string}'. ".format(string=option) +
-                       "Please restore you configuration file back to default if necessary.")
+    except KeyError:
+        raise KeyError("Missed strings in configuration file: '{string}'. ".format(string=option)
+                       + "Please restore you configuration file back to default if necessary.")
     if argv or kwargs:
         try:
             formatted = string.format(*argv, **kwargs)
             return formatted
         except KeyError as e:
             raise KeyError(
-                "Missed/Unexpected placeholder {{{placeholder}}} in string '{string}'. ".format(placeholder=str(e).strip("'"), string=option) +
-                "Please restore you configuration file back to default if necessary.")
-        except TypeError as e:
+                "Missed/Unexpected placeholder {{{placeholder}}} in string '{string}'. ".format(placeholder=str(e).strip("'"), string=option)
+                + "Please restore you configuration file back to default if necessary.")
+        except TypeError:
             raise KeyError(
-                "Missed placeholder in string '{string}'. ".format(string=option) +
-                "Please restore you configuration file back to default if necessary.")
+                "Missed placeholder in string '{string}'. ".format(string=option)
+                + "Please restore you configuration file back to default if necessary.")
     else:
         return string
 
+
 def commands(command):
-    string = ""
     try:
         string = var.config.get("commands", command)
         return string
-    except KeyError as e:
-        raise KeyError("Missed command in configuration file: '{string}'. ".format(string=command) +
-                       "Please restore you configuration file back to default if necessary.")
+    except KeyError:
+        raise KeyError("Missed command in configuration file: '{string}'. ".format(string=command)
+                       + "Please restore you configuration file back to default if necessary.")
diff --git a/database.py b/database.py
index f3096b1..c4815a1 100644
--- a/database.py
+++ b/database.py
@@ -2,17 +2,19 @@ import sqlite3
 import json
 import datetime
 
+
 class DatabaseError(Exception):
     pass
 
+
 class SettingsDatabase:
     version = 1
+
     def __init__(self, db_path):
         self.db_path = db_path
 
         # connect
         conn = sqlite3.connect(self.db_path)
-        cursor = conn.cursor()
 
         self.db_version_check_and_create()
 
@@ -57,9 +59,9 @@ class SettingsDatabase:
                        "value TEXT, "
                        "UNIQUE(section, option))")
         cursor.execute("INSERT INTO botamusique (section, option, value) "
-                       "VALUES (?, ?, ?)" , ("bot", "db_version", "1"))
+                       "VALUES (?, ?, ?)", ("bot", "db_version", "1"))
         cursor.execute("INSERT INTO botamusique (section, option, value) "
-                       "VALUES (?, ?, ?)" , ("bot", "music_db_version", "0"))
+                       "VALUES (?, ?, ?)", ("bot", "music_db_version", "0"))
         conn.commit()
         conn.close()
 
@@ -90,7 +92,7 @@ class SettingsDatabase:
         conn = sqlite3.connect(self.db_path)
         cursor = conn.cursor()
         cursor.execute("INSERT OR REPLACE INTO botamusique (section, option, value) "
-                       "VALUES (?, ?, ?)" , (section, option, value))
+                       "VALUES (?, ?, ?)", (section, option, value))
         conn.commit()
         conn.close()
 
@@ -214,7 +216,7 @@ class MusicDatabase:
         conn = sqlite3.connect(self.db_path)
         cursor = conn.cursor()
         results = cursor.execute("SELECT id, type, title, metadata, tags FROM music "
-                                "WHERE %s" % condition_str, filler).fetchall()
+                                 "WHERE %s" % condition_str, filler).fetchall()
         conn.close()
 
         return self._result_to_dict(results)
@@ -227,7 +229,6 @@ class MusicDatabase:
             condition.append('LOWER(title) LIKE ?')
             filler.append("%{:s}%".format(keyword.lower()))
 
-
         condition_str = " AND ".join(condition)
 
         conn = sqlite3.connect(self.db_path)
@@ -246,7 +247,6 @@ class MusicDatabase:
             condition.append('LOWER(tags) LIKE ?')
             filler.append("%{:s},%".format(tag.lower()))
 
-
         condition_str = " AND ".join(condition)
 
         conn = sqlite3.connect(self.db_path)
@@ -284,7 +284,6 @@ class MusicDatabase:
 
         return self._result_to_dict(results)
 
-
     def _result_to_dict(self, results):
         if len(results) > 0:
             music_dicts = []
@@ -320,11 +319,10 @@ class MusicDatabase:
         conn = sqlite3.connect(self.db_path)
         cursor = conn.cursor()
         cursor.execute("DELETE FROM music "
-                                 "WHERE %s" % condition_str, filler)
+                       "WHERE %s" % condition_str, filler)
         conn.commit()
         conn.close()
 
-
     def drop_table(self):
         conn = sqlite3.connect(self.db_path)
         cursor = conn.cursor()
diff --git a/interface.py b/interface.py
index a6c0127..6022072 100644
--- a/interface.py
+++ b/interface.py
@@ -16,7 +16,7 @@ import time
 
 
 class ReverseProxied(object):
-    '''Wrap the application in this middleware and configure the
+    """Wrap the application in this middleware and configure the
     front-end server to add these headers, to let you quietly bind
     this to a URL other than / and to an HTTP scheme that is
     different than what is used locally.
@@ -31,7 +31,7 @@ class ReverseProxied(object):
         }
 
     :param app: the WSGI application
-    '''
+    """
 
     def __init__(self, app):
         self.app = app
@@ -57,6 +57,7 @@ web = Flask(__name__)
 log = logging.getLogger("bot")
 user = 'Remote Control'
 
+
 def init_proxy():
     global web
     if var.is_proxified:
@@ -64,19 +65,21 @@ def init_proxy():
 
 # https://stackoverflow.com/questions/29725217/password-protect-one-webpage-in-flask-app
 
+
 def check_auth(username, password):
     """This function is called to check if a username /
     password combination is valid.
     """
     return username == var.config.get("webinterface", "user") and password == var.config.get("webinterface", "password")
 
+
 def authenticate():
     """Sends a 401 response that enables basic auth"""
     global log
-    return Response(
-    'Could not verify your access level for that URL.\n'
-    'You have to login with proper credentials', 401,
-    {'WWW-Authenticate': 'Basic realm="Login Required"'})
+    return Response('Could not verify your access level for that URL.\n'
+                    'You have to login with proper credentials', 401,
+                    {'WWW-Authenticate': 'Basic realm="Login Required"'})
+
 
 def requires_auth(f):
     @wraps(f)
@@ -90,6 +93,7 @@ def requires_auth(f):
         return f(*args, **kwargs)
     return decorated
 
+
 def tag_color(tag):
     num = hash(tag) % 8
     if num == 0:
@@ -109,14 +113,15 @@ def tag_color(tag):
     elif num == 7:
         return "dark"
 
+
 def build_tags_color_lookup():
     color_lookup = {}
     for tag in var.music_db.query_all_tags():
         color_lookup[tag] = tag_color(tag)
 
-
     return color_lookup
 
+
 def build_path_tags_lookup():
     path_tags_lookup = {}
     ids = list(var.cache.file_id_lookup.values())
@@ -128,11 +133,13 @@ def build_path_tags_lookup():
 
     return path_tags_lookup
 
+
 def recur_dir(dirobj):
     for name, dir in dirobj.get_subdirs().items():
         print(dirobj.fullpath + "/" + name)
         recur_dir(dir)
 
+
 @web.route("/", methods=['GET'])
 @requires_auth
 def index():
@@ -153,21 +160,22 @@ def index():
                            paused=var.bot.is_pause,
                            )
 
+
 @web.route("/playlist", methods=['GET'])
 @requires_auth
 def playlist():
     if len(var.playlist) == 0:
         return jsonify({'items': [render_template('playlist.html',
-                               m=False,
-                               index=-1
-                               )]
+                                                  m=False,
+                                                  index=-1
+                                                  )]
                         })
 
     tags_color_lookup = build_tags_color_lookup()
     items = []
 
     for index, item_wrapper in enumerate(var.playlist):
-         items.append(render_template('playlist.html',
+        items.append(render_template('playlist.html',
                                      index=index,
                                      tags_color_lookup=tags_color_lookup,
                                      m=item_wrapper.item(),
@@ -175,7 +183,8 @@ def playlist():
                                      )
                      )
 
-    return jsonify({ 'items': items })
+    return jsonify({'items': items})
+
 
 def status():
     if len(var.playlist) > 0:
@@ -197,7 +206,7 @@ def post():
 
     if request.method == 'POST':
         if request.form:
-            log.debug("web: Post request from %s: %s" % ( request.remote_addr, str(request.form)))
+            log.debug("web: Post request from %s: %s" % (request.remote_addr, str(request.form)))
         if 'add_file_bottom' in request.form and ".." not in request.form['add_file_bottom']:
             path = var.music_folder + request.form['add_file_bottom']
             if os.path.isfile(path):
@@ -231,15 +240,13 @@ def post():
 
                 music_wrappers = list(map(
                     lambda file:
-                    get_cached_wrapper_by_id(var.bot, var.cache.file_id_lookup[folder + file], user),
-                files))
+                    get_cached_wrapper_by_id(var.bot, var.cache.file_id_lookup[folder + file], user), files))
 
                 var.playlist.extend(music_wrappers)
 
                 for music_wrapper in music_wrappers:
                     log.info('web: add to playlist: ' + music_wrapper.format_debug_string())
 
-
         elif 'add_url' in request.form:
             music_wrapper = get_cached_wrapper_from_scrap(var.bot, type='url', url=request.form['add_url'], user=user)
             var.playlist.append(music_wrapper)
@@ -279,7 +286,6 @@ def post():
                 else:
                     var.playlist.remove(index)
 
-
         elif 'play_music' in request.form:
             music_wrapper = var.playlist[int(request.form['play_music'])]
             log.info("web: jump to: " + music_wrapper.format_debug_string())
@@ -358,6 +364,7 @@ def post():
 
     return status()
 
+
 @web.route('/upload', methods=["POST"])
 def upload():
     global log
@@ -366,7 +373,7 @@ def upload():
     if not files:
         return redirect("./", code=406)
 
-    #filename = secure_filename(file.filename).strip()
+    # filename = secure_filename(file.filename).strip()
     for file in files:
         filename = file.filename
         if filename == '':
@@ -385,7 +392,7 @@ def upload():
 
         if "audio" in file.mimetype:
             storagepath = os.path.abspath(os.path.join(var.music_folder, targetdir))
-            print('storagepath:',storagepath)
+            print('storagepath:', storagepath)
             if not storagepath.startswith(os.path.abspath(var.music_folder)):
                 return redirect("./", code=406)
 
diff --git a/librb/radiobrowser.py b/librb/radiobrowser.py
index d2b55d6..9499c8f 100644
--- a/librb/radiobrowser.py
+++ b/librb/radiobrowser.py
@@ -2,28 +2,32 @@ from librb.rbRadios import RadioBrowser
 
 rb = RadioBrowser()
 
+
 def getstations_byname(query):
     results = rb.stations_byname(query)
     stations = []
     for st in results:
         try:
-            station = {'stationname': st['name'], 'id':st['id'], 'codec':st['codec'], 'bitrate':st['bitrate'], 'country':st['country'], 'homepage':st['homepage'], 'genre':st['tags']}
+            station = {'stationname': st['name'], 'id': st['id'], 'codec': st['codec'], 'bitrate': st['bitrate'], 'country': st['country'], 'homepage': st['homepage'], 'genre': st['tags']}
             stations.append(station)
         except:
             pass
     return stations
 
+
 def geturl_byid(id):
     url = rb.playable_station(id)['url']
-    if url != None:
+    if url is not None:
         return url
     else:
         return "-1"
 
+
 def getstationname_byid(id):
     return rb.stations_byid(id)
-    
+
+
 if __name__ == "__main__":
     r = getstations_byname('r.sh')
     stationinfo = getstationname_byid(96748)
-    pass
\ No newline at end of file
+    pass
diff --git a/librb/rbRadios.py b/librb/rbRadios.py
index 25af8d5..77a38ed 100644
--- a/librb/rbRadios.py
+++ b/librb/rbRadios.py
@@ -1,8 +1,5 @@
 import requests
 
-from xml.etree import ElementTree
-from urllib.parse import urljoin
-
 from librb.rbConstants import endpoints, BASE_URL
 
 
@@ -179,5 +176,4 @@ class RadioBrowser:
         assert isinstance(params, dict), "params is not a dict"
         kwargs["params"] = params
         endpoint = self.builder.produce_endpoint(endpoint="station_search")
-        return request(endpoint, **kwargs)
-        
\ No newline at end of file
+        return request(endpoint, **kwargs)
\ No newline at end of file
diff --git a/media/cache.py b/media/cache.py
index b2d5e71..1373258 100644
--- a/media/cache.py
+++ b/media/cache.py
@@ -1,11 +1,10 @@
 import logging
 import os
 
-from database import MusicDatabase
 import json
 import threading
 
-from media.item import item_builders, item_loaders, item_id_generators, dict_to_item, dicts_to_items
+from media.item import item_builders, item_id_generators, dict_to_item
 from database import MusicDatabase
 import variables as var
 import util
@@ -18,9 +17,10 @@ class MusicCache(dict):
         self.log = logging.getLogger("bot")
         self.dir = None
         self.files = []
+        self.file_id_lookup = {}
         self.dir_lock = threading.Lock()
 
-    def get_item_by_id(self, bot, id): # Why all these functions need a bot? Because it need the bot to send message!
+    def get_item_by_id(self, bot, id):  # Why all these functions need a bot? Because it need the bot to send message!
         if id in self:
             return self[id]
 
@@ -32,9 +32,8 @@ class MusicCache(dict):
             return item
         else:
             return None
-            #print(id)
-            #raise KeyError("Unable to fetch item from the database! Please try to refresh the cache by !recache.")
-
+            # print(id)
+            # raise KeyError("Unable to fetch item from the database! Please try to refresh the cache by !recache.")
 
     def get_item(self, bot, **kwargs):
         # kwargs should provide type and id, and parameters to build the item if not existed in the library.
@@ -55,7 +54,7 @@ class MusicCache(dict):
             return item
 
         # if not in the database, build one
-        self[id] = item_builders[kwargs['type']](bot, **kwargs) # newly built item will not be saved immediately
+        self[id] = item_builders[kwargs['type']](bot, **kwargs)  # newly built item will not be saved immediately
         return self[id]
 
     def get_items_by_tags(self, bot, tags):
@@ -112,7 +111,6 @@ class MusicCache(dict):
         self.dir_lock.acquire()
         self.log.info("library: rebuild directory cache")
         self.files = []
-        self.file_id_lookup = {}
         files = util.get_recursive_file_list_sorted(var.music_folder)
         self.dir = util.Dir(var.music_folder)
         for file in files:
@@ -254,4 +252,4 @@ def get_cached_wrappers_by_tags(bot, tags, user):
     ret = []
     for item in items:
         ret.append(CachedItemWrapper(var.cache, item.id, item.type, user))
-    return ret
\ No newline at end of file
+    return ret
diff --git a/media/file.py b/media/file.py
index 38014d6..4718ea3 100644
--- a/media/file.py
+++ b/media/file.py
@@ -1,4 +1,3 @@
-import logging
 import os
 import re
 from io import BytesIO
@@ -6,9 +5,7 @@ import base64
 import hashlib
 import mutagen
 from PIL import Image
-import json
 
-import util
 import variables as var
 from media.item import BaseItem, item_builders, item_loaders, item_id_generators
 import constants
@@ -24,15 +21,19 @@ type : file
     user
 '''
 
+
 def file_item_builder(bot, **kwargs):
     return FileItem(bot, kwargs['path'])
 
+
 def file_item_loader(bot, _dict):
     return FileItem(bot, "", _dict)
 
+
 def file_item_id_generator(**kwargs):
     return hashlib.md5(kwargs['path'].encode()).hexdigest()
 
+
 item_builders['file'] = file_item_builder
 item_loaders['file'] = file_item_loader
 item_id_generators['file'] = file_item_id_generator
@@ -74,12 +75,12 @@ class FileItem(BaseItem):
             self.send_client_message(constants.strings('file_missed', file=self.path))
             return False
 
-        #self.version += 1 # 0 -> 1, notify the wrapper to save me when validate() is visited the first time
+        # self.version += 1 # 0 -> 1, notify the wrapper to save me when validate() is visited the first time
         self.ready = "yes"
         return True
 
     def _get_info_from_tag(self):
-        match = re.search("(.+)\.(.+)", self.uri())
+        match = re.search(r"(.+)\.(.+)", self.uri())
         assert match is not None
 
         file_no_ext = match[1]
@@ -153,17 +154,17 @@ class FileItem(BaseItem):
 
     def format_song_string(self, user):
         return constants.strings("file_item",
-                                    title=self.title,
-                                    artist=self.artist if self.artist else '??',
-                                    user=user
-                                    )
+                                 title=self.title,
+                                 artist=self.artist if self.artist else '??',
+                                 user=user
+                                 )
 
     def format_current_playing(self, user):
         display = constants.strings("now_playing", item=self.format_song_string(user))
         if self.thumbnail:
             thumbnail_html = '<img width="80" src="data:image/jpge;base64,' + \
                              self.thumbnail + '"/>'
-            display += "<br />" +  thumbnail_html
+            display += "<br />" + thumbnail_html
 
         return display
 
diff --git a/media/item.py b/media/item.py
index 5ff5fff..bd09a81 100644
--- a/media/item.py
+++ b/media/item.py
@@ -1,33 +1,27 @@
 import logging
-import threading
-import os
-import re
-from io import BytesIO
-import base64
-import hashlib
-import mutagen
-from PIL import Image
-
-import util
-import variables as var
 
 item_builders = {}
 item_loaders = {}
 item_id_generators = {}
 
+
 def example_builder(bot, **kwargs):
     return BaseItem(bot)
 
+
 def example_loader(bot, _dict):
     return BaseItem(bot, from_dict=_dict)
 
+
 def example_id_generator(**kwargs):
     return ""
 
+
 item_builders['base'] = example_builder
 item_loaders['base'] = example_loader
 item_id_generators['base'] = example_id_generator
 
+
 def dicts_to_items(bot, music_dicts):
     items = []
     for music_dict in music_dicts:
@@ -35,6 +29,7 @@ def dicts_to_items(bot, music_dicts):
         items.append(item_loaders[type](bot, music_dict))
     return items
 
+
 def dict_to_item(bot, music_dict):
     type = music_dict['type']
     return item_loaders[type](bot, music_dict)
@@ -48,11 +43,11 @@ class BaseItem:
         self.title = ""
         self.path = ""
         self.tags = []
-        self.version = 0 # if version increase, wrapper will re-save this item
+        self.version = 0  # if version increase, wrapper will re-save this item
 
         if from_dict is None:
             self.id = ""
-            self.ready = "pending" # pending - is_valid() -> validated - prepare() -> yes, failed
+            self.ready = "pending"  # pending - is_valid() -> validated - prepare() -> yes, failed
         else:
             self.id = from_dict['id']
             self.ready = from_dict['ready']
@@ -110,6 +105,4 @@ class BaseItem:
             self.bot.send_msg(msg)
 
     def to_dict(self):
-        return {"type" : self.type, "id": self.id, "ready": self.ready, "path": self.path, "tags": self.tags}
-
-
+        return {"type": self.type, "id": self.id, "ready": self.ready, "path": self.path, "tags": self.tags}
diff --git a/media/playlist.py b/media/playlist.py
index 4f49228..d078fa3 100644
--- a/media/playlist.py
+++ b/media/playlist.py
@@ -162,12 +162,12 @@ class BasePlaylist(list):
 
     def randomize(self):
         # current_index will lose track after shuffling, thus we take current music out before shuffling
-        #current = self.current_item()
-        #del self[self.current_index]
+        # current = self.current_item()
+        # del self[self.current_index]
 
         random.shuffle(self)
 
-        #self.insert(0, current)
+        # self.insert(0, current)
         self.current_index = -1
         self.version += 1
 
@@ -183,7 +183,7 @@ class BasePlaylist(list):
         var.db.set("playlist", "current_index", self.current_index)
 
         for index, music in enumerate(self):
-            var.db.set("playlist_item", str(index), json.dumps({'id': music.id, 'user': music.user }))
+            var.db.set("playlist_item", str(index), json.dumps({'id': music.id, 'user': music.user}))
 
     def load(self):
         current_index = var.db.getint("playlist", "current_index", fallback=-1)
@@ -212,7 +212,7 @@ class BasePlaylist(list):
 
     def start_async_validating(self):
         if not self.validating_thread_lock.locked():
-            time.sleep(0.1) # Just avoid validation finishes too fast and delete songs while something is reading it.
+            time.sleep(0.1)  # Just avoid validation finishes too fast and delete songs while something is reading it.
             th = threading.Thread(target=self._check_valid, name="Validating")
             th.daemon = True
             th.start()
@@ -359,4 +359,3 @@ class AutoPlaylist(OneshotPlaylist):
         if len(self) == 0:
             self.refresh()
         return super().next()
-
diff --git a/media/radio.py b/media/radio.py
index e825055..65b1c59 100644
--- a/media/radio.py
+++ b/media/radio.py
@@ -11,16 +11,16 @@ import constants
 
 log = logging.getLogger("bot")
 
+
 def get_radio_server_description(url):
     global log
 
     log.debug("radio: fetching radio server description")
-    p = re.compile('(https?\:\/\/[^\/]*)', re.IGNORECASE)
+    p = re.compile('(https?://[^/]*)', re.IGNORECASE)
     res = re.search(p, url)
     base_url = res.group(1)
     url_icecast = base_url + '/status-json.xsl'
     url_shoutcast = base_url + '/stats?json=1'
-    title_server = None
     try:
         r = requests.get(url_shoutcast, timeout=10)
         data = r.json()
@@ -30,7 +30,7 @@ def get_radio_server_description(url):
     except (requests.exceptions.ConnectionError,
             requests.exceptions.HTTPError,
             requests.exceptions.ReadTimeout,
-            requests.exceptions.Timeout) as e:
+            requests.exceptions.Timeout):
         error_traceback = traceback.format_exc()
         error = error_traceback.rstrip().split("\n")[-1]
         log.debug("radio: unsuccessful attempts on fetching radio description (shoutcast): " + error)
@@ -51,7 +51,7 @@ def get_radio_server_description(url):
     except (requests.exceptions.ConnectionError,
             requests.exceptions.HTTPError,
             requests.exceptions.ReadTimeout,
-            requests.exceptions.Timeout) as e:
+            requests.exceptions.Timeout):
         error_traceback = traceback.format_exc()
         error = error_traceback.rstrip().split("\n")[-1]
         log.debug("radio: unsuccessful attempts on fetching radio description (icecast): " + error)
@@ -81,7 +81,7 @@ def get_radio_title(url):
             requests.exceptions.HTTPError,
             requests.exceptions.ReadTimeout,
             requests.exceptions.Timeout,
-            KeyError) as e:
+            KeyError):
         log.debug("radio: unsuccessful attempts on fetching radio title (icy)")
     return url
 
@@ -92,12 +92,15 @@ def radio_item_builder(bot, **kwargs):
     else:
         return RadioItem(bot, kwargs['url'], '')
 
+
 def radio_item_loader(bot, _dict):
     return RadioItem(bot, "", "", _dict)
 
+
 def radio_item_id_generator(**kwargs):
     return hashlib.md5(kwargs['url'].encode()).hexdigest()
 
+
 item_builders['radio'] = radio_item_builder
 item_loaders['radio'] = radio_item_loader
 item_id_generators['radio'] = radio_item_id_generator
@@ -109,7 +112,7 @@ class RadioItem(BaseItem):
             super().__init__(bot)
             self.url = url
             if not name:
-                self.title = get_radio_server_description(self.url) # The title of the radio station
+                self.title = get_radio_server_description(self.url)  # The title of the radio station
             else:
                 self.title = name
             self.id = hashlib.md5(url.encode()).hexdigest()
@@ -121,7 +124,7 @@ class RadioItem(BaseItem):
         self.type = "radio"
 
     def validate(self):
-        self.version += 1 # 0 -> 1, notify the wrapper to save me when validate() is visited the first time
+        self.version += 1  # 0 -> 1, notify the wrapper to save me when validate() is visited the first time
         return True
 
     def is_ready(self):
@@ -146,8 +149,8 @@ class RadioItem(BaseItem):
     def format_song_string(self, user):
         return constants.strings("radio_item",
                                  url=self.url,
-                                 title=get_radio_title(self.url), # the title of current song
-                                 name=self.title, # the title of radio station
+                                 title=get_radio_title(self.url),  # the title of current song
+                                 name=self.title,  # the title of radio station
                                  user=user
                                  )
 
@@ -159,6 +162,3 @@ class RadioItem(BaseItem):
 
     def display_type(self):
         return constants.strings("radio")
-
-
-
diff --git a/media/url.py b/media/url.py
index 8b30585..f5f4163 100644
--- a/media/url.py
+++ b/media/url.py
@@ -17,15 +17,19 @@ import media.system
 
 log = logging.getLogger("bot")
 
+
 def url_item_builder(bot, **kwargs):
     return URLItem(bot, kwargs['url'])
 
+
 def url_item_loader(bot, _dict):
     return URLItem(bot, "", _dict)
 
+
 def url_item_id_generator(**kwargs):
     return hashlib.md5(kwargs['url'].encode()).hexdigest()
 
+
 item_builders['url'] = url_item_builder
 item_loaders['url'] = url_item_loader
 item_id_generators['url'] = url_item_id_generator
@@ -97,7 +101,7 @@ class URLItem(BaseItem):
             return False
         else:
             self.ready = "validated"
-            self.version += 1 # notify wrapper to save me
+            self.version += 1  # notify wrapper to save me
             return True
 
     # Run in a other thread
@@ -145,8 +149,6 @@ class URLItem(BaseItem):
         self.ready = "preparing"
 
         self.log.info("bot: downloading url (%s) %s " % (self.title, self.url))
-        ydl_opts = ""
-
         ydl_opts = {
             'format': 'bestaudio/best',
             'outtmpl': save_path,
@@ -166,7 +168,7 @@ class URLItem(BaseItem):
             for i in range(attempts):
                 self.log.info("bot: download attempts %d / %d" % (i+1, attempts))
                 try:
-                    info = ydl.extract_info(self.url)
+                    ydl.extract_info(self.url)
                     download_succeed = True
                     break
                 except:
@@ -181,7 +183,7 @@ class URLItem(BaseItem):
                     "bot: finished downloading url (%s) %s, saved to %s." % (self.title, self.url, self.path))
                 self.downloading = False
                 self._read_thumbnail_from_file(base_path + ".jpg")
-                self.version += 1 # notify wrapper to save me
+                self.version += 1  # notify wrapper to save me
                 return True
             else:
                 for f in glob.glob(base_path + "*"):
@@ -214,7 +216,6 @@ class URLItem(BaseItem):
 
         return dict
 
-
     def format_debug_string(self):
         return "[url] {title} ({url})".format(
             title=self.title,
@@ -224,9 +225,9 @@ class URLItem(BaseItem):
     def format_song_string(self, user):
         if self.ready in ['validated', 'yes']:
             return constants.strings("url_item",
-                                        title=self.title if self.title else "??",
-                                        url=self.url,
-                                        user=user)
+                                     title=self.title if self.title else "??",
+                                     url=self.url,
+                                     user=user)
         return self.url
 
     def format_current_playing(self, user):
@@ -235,7 +236,7 @@ class URLItem(BaseItem):
         if self.thumbnail:
             thumbnail_html = '<img width="80" src="data:image/jpge;base64,' + \
                              self.thumbnail + '"/>'
-            display += "<br />" +  thumbnail_html
+            display += "<br />" + thumbnail_html
 
         return display
 
diff --git a/media/url_from_playlist.py b/media/url_from_playlist.py
index a08d948..99b6007 100644
--- a/media/url_from_playlist.py
+++ b/media/url_from_playlist.py
@@ -1,11 +1,10 @@
 import youtube_dl
 import constants
-import media
 import variables as var
-import hashlib
 from media.item import item_builders, item_loaders, item_id_generators
 from media.url import URLItem, url_item_id_generator
 
+
 def get_playlist_info(url, start_index=0, user=""):
     items = []
     ydl_opts = {
@@ -63,6 +62,7 @@ def playlist_url_item_builder(bot, **kwargs):
 def playlist_url_item_loader(bot, _dict):
     return PlaylistURLItem(bot, "", "", "", "", _dict)
 
+
 item_builders['url_from_playlist'] = playlist_url_item_builder
 item_loaders['url_from_playlist'] = playlist_url_item_loader
 item_id_generators['url_from_playlist'] = url_item_id_generator
@@ -98,11 +98,11 @@ class PlaylistURLItem(URLItem):
 
     def format_song_string(self, user):
         return constants.strings("url_from_playlist_item",
-                                    title=self.title,
-                                    url=self.url,
-                                    playlist_url=self.playlist_url,
-                                    playlist=self.playlist_title,
-                                    user=user)
+                                 title=self.title,
+                                 url=self.url,
+                                 playlist_url=self.playlist_url,
+                                 playlist=self.playlist_title,
+                                 user=user)
 
     def format_current_playing(self, user):
         display = constants.strings("now_playing", item=self.format_song_string(user))
@@ -110,7 +110,7 @@ class PlaylistURLItem(URLItem):
         if self.thumbnail:
             thumbnail_html = '<img width="80" src="data:image/jpge;base64,' + \
                              self.thumbnail + '"/>'
-            display += "<br />" +  thumbnail_html
+            display += "<br />" + thumbnail_html
 
         return display
 
diff --git a/mumbleBot.py b/mumbleBot.py
index 4ee7d66..ec63bb4 100644
--- a/mumbleBot.py
+++ b/mumbleBot.py
@@ -14,8 +14,6 @@ import os
 import os.path
 import pymumble.pymumble_py3 as pymumble
 import variables as var
-import hashlib
-import youtube_dl
 import logging
 import logging.handlers
 import traceback
@@ -25,9 +23,6 @@ import util
 import command
 import constants
 from database import SettingsDatabase, MusicDatabase
-import media.url
-import media.file
-import media.radio
 import media.system
 from media.playlist import BasePlaylist
 from media.cache import MusicCache
@@ -74,8 +69,8 @@ class MumbleBot:
         self.song_start_at = -1
         self.last_ffmpeg_err = ""
         self.read_pcm_size = 0
-        #self.download_threads = []
-        self.wait_for_downloading = False # flag for the loop are waiting for download to complete in the other thread
+        # self.download_threads = []
+        self.wait_for_downloading = False  # flag for the loop are waiting for download to complete in the other thread
 
         if var.config.getboolean("webinterface", "enabled"):
             wi_addr = var.config.get("webinterface", "listening_addr")
@@ -151,7 +146,7 @@ class MumbleBot:
             self.ducking_volume = var.db.getfloat("bot", "ducking_volume", fallback=self.ducking_volume)
             self.ducking_threshold = var.config.getfloat("bot", "ducking_threshold", fallback=5000)
             self.ducking_threshold = var.db.getfloat("bot", "ducking_threshold", fallback=self.ducking_threshold)
-            self.mumble.callbacks.set_callback(pymumble.constants.PYMUMBLE_CLBK_SOUNDRECEIVED, \
+            self.mumble.callbacks.set_callback(pymumble.constants.PYMUMBLE_CLBK_SOUNDRECEIVED,
                                                self.ducking_sound_received)
             self.mumble.set_receive_sound(True)
 
@@ -173,7 +168,7 @@ class MumbleBot:
         self.nb_exit += 1
 
         if var.config.getboolean('bot', 'save_playlist', fallback=True) \
-                    and var.config.get("bot", "save_music_library", fallback=True):
+                and var.config.get("bot", "save_music_library", fallback=True):
             self.log.info("bot: save playlist into database")
             var.playlist.save()
 
@@ -191,9 +186,9 @@ class MumbleBot:
         for command in cmds:
             command = command.strip()
             if command:
-                self.cmd_handle[command] = { 'handle': handle,
-                                             'partial_match': not no_partial_match,
-                                             'access_outside_channel': access_outside_channel}
+                self.cmd_handle[command] = {'handle': handle,
+                                            'partial_match': not no_partial_match,
+                                            'access_outside_channel': access_outside_channel}
                 self.log.debug("bot: command added: " + command)
 
     def set_comment(self):
@@ -247,7 +242,6 @@ class MumbleBot:
                             constants.strings('url_ban'))
                         return
 
-
             command_exc = ""
             try:
                 if command in self.cmd_handle:
@@ -278,7 +272,7 @@ class MumbleBot:
                                 and not self.is_admin(user) \
                                 and not var.config.getboolean('bot', 'allow_other_channel_message') \
                                 and self.mumble.users[text.actor]['channel_id'] != self.mumble.users.myself[
-                            'channel_id']:
+                                'channel_id']:
                             self.mumble.users[text.actor].send_text_message(
                                 constants.strings('not_in_my_channel'))
                             return
@@ -319,7 +313,7 @@ class MumbleBot:
     def launch_music(self):
         if var.playlist.is_empty():
             return
-        assert self.wait_for_downloading == False
+        assert self.wait_for_downloading is False
 
         music_wrapper = var.playlist.current_item()
         uri = music_wrapper.uri()
@@ -341,7 +335,7 @@ class MumbleBot:
         # The ffmpeg process is a thread
         # prepare pipe for catching stderr of ffmpeg
         pipe_rd, pipe_wd = os.pipe()
-        util.pipe_no_wait(pipe_rd) # Let the pipe work in non-blocking mode
+        util.pipe_no_wait(pipe_rd)  # Let the pipe work in non-blocking mode
         self.thread_stderr = os.fdopen(pipe_rd)
         self.thread = sp.Popen(command, stdout=sp.PIPE, stderr=pipe_wd, bufsize=480)
         self.is_pause = False
@@ -367,7 +361,6 @@ class MumbleBot:
                 var.playlist.remove_by_id(next.id)
                 var.cache.free_and_delete(next.id)
 
-
     # =======================
     #          Loop
     # =======================
@@ -490,14 +483,14 @@ class MumbleBot:
             if rms < self.ducking_threshold:
                 print('%6d/%6d  ' % (rms, self._max_rms) + '-'*int(rms/200), end='\r')
             else:
-                print('%6d/%6d  ' % (rms, self._max_rms) + '-'*int(self.ducking_threshold/200) \
+                print('%6d/%6d  ' % (rms, self._max_rms) + '-'*int(self.ducking_threshold/200)
                       + '+'*int((rms - self.ducking_threshold)/200), end='\r')
 
         if rms > self.ducking_threshold:
             if self.on_ducking is False:
                 self.log.debug("bot: ducking triggered")
                 self.on_ducking = True
-            self.ducking_release = time.time() + 1 # ducking release after 1s
+            self.ducking_release = time.time() + 1  # ducking release after 1s
 
     # =======================
     #      Play Control
@@ -558,7 +551,6 @@ class MumbleBot:
         command = ("ffmpeg", '-v', ffmpeg_debug, '-nostdin', '-ss', "%f" % self.playhead, '-i',
                    uri, '-ac', '1', '-f', 's16le', '-ar', '48000', '-')
 
-
         if var.config.getboolean('bot', 'announce_current_music'):
             self.send_msg(var.playlist.current_item().format_current_playing())
 
@@ -566,13 +558,12 @@ class MumbleBot:
         # The ffmpeg process is a thread
         # prepare pipe for catching stderr of ffmpeg
         pipe_rd, pipe_wd = os.pipe()
-        util.pipe_no_wait(pipe_rd) # Let the pipe work in non-blocking mode
+        util.pipe_no_wait(pipe_rd)  # Let the pipe work in non-blocking mode
         self.thread_stderr = os.fdopen(pipe_rd)
         self.thread = sp.Popen(command, stdout=sp.PIPE, stderr=pipe_wd, bufsize=480)
         self.last_volume_cycle_time = time.time()
         self.pause_at_id = ""
 
-
     # TODO: this is a temporary workaround for issue #44 of pymumble.
     def _clear_pymumble_soundqueue(self):
         for id, user in self.mumble.users.items():
@@ -582,7 +573,6 @@ class MumbleBot:
         self.log.debug("bot: pymumble soundqueue cleared.")
 
 
-
 def start_web_interface(addr, port):
     global formatter
     import interface
@@ -590,9 +580,8 @@ def start_web_interface(addr, port):
     # setup logger
     werkzeug_logger = logging.getLogger('werkzeug')
     logfile = util.solve_filepath(var.config.get('webinterface', 'web_logfile'))
-    handler = None
     if logfile:
-        handler = logging.handlers.RotatingFileHandler(logfile, mode='a', maxBytes=10240) # Rotate after 10KB
+        handler = logging.handlers.RotatingFileHandler(logfile, mode='a', maxBytes=10240)  # Rotate after 10KB
     else:
         handler = logging.StreamHandler()
 
@@ -657,7 +646,7 @@ if __name__ == '__main__':
     logfile = util.solve_filepath(var.config.get('bot', 'logfile'))
     handler = None
     if logfile:
-        handler = logging.handlers.RotatingFileHandler(logfile, mode='a', maxBytes=10240) # Rotate after 10KB
+        handler = logging.handlers.RotatingFileHandler(logfile, mode='a', maxBytes=10240)  # Rotate after 10KB
     else:
         handler = logging.StreamHandler()
 
diff --git a/util.py b/util.py
index 447b5c6..af763d6 100644
--- a/util.py
+++ b/util.py
@@ -6,23 +6,16 @@ import magic
 import os
 import sys
 import variables as var
-import constants
 import zipfile
 import requests
-import mutagen
 import re
 import subprocess as sp
 import logging
 import youtube_dl
 from importlib import reload
-from PIL import Image
-from io import BytesIO
 from sys import platform
 import traceback
-import urllib.parse, urllib.request, urllib.error
-import base64
-import media
-import media.radio
+import urllib.request
 from packaging import version
 
 log = logging.getLogger("bot")
@@ -65,6 +58,7 @@ def get_recursive_file_list_sorted(path):
     filelist.sort()
     return filelist
 
+
 # - zips all files of the given zippath (must be a directory)
 # - returns the absolute path of the created zip file
 # - zip file will be in the applications tmp folder (according to configuration)
@@ -172,7 +166,7 @@ def url_unban(url):
 
 
 def pipe_no_wait(pipefd):
-    ''' Used to fetch the STDERR of ffmpeg. pipefd is the file descriptor returned from os.pipe()'''
+    """ Used to fetch the STDERR of ffmpeg. pipefd is the file descriptor returned from os.pipe()"""
     if platform == "linux" or platform == "linux2" or platform == "darwin":
         import fcntl
         import os
@@ -309,18 +303,19 @@ def get_url_from_input(string):
     else:
         return False
 
+
 def youtube_search(query):
     global log
 
     try:
         r = requests.get("https://www.youtube.com/results", params={'search_query': query}, timeout=5)
-        results = re.findall("watch\?v=(.*?)\".*?title=\"(.*?)\".*?"
-                             "(?:user|channel).*?>(.*?)<", r.text) # (id, title, uploader)
+        results = re.findall(r"watch\?v=(.*?)\".*?title=\"(.*?)\".*?"
+                             "(?:user|channel).*?>(.*?)<", r.text)  # (id, title, uploader)
 
         if len(results) > 0:
             return results
 
-    except (requests.exceptions.ConnectionError, requests.exceptions.HTTPError, requests.exceptions.Timeout) as e:
+    except (requests.exceptions.ConnectionError, requests.exceptions.HTTPError, requests.exceptions.Timeout):
         error_traceback = traceback.format_exc().split("During")[0]
         log.error("util: youtube query failed with error:\n %s" % error_traceback)
         return False