diff --git a/couchpotato/core/downloaders/base.py b/couchpotato/core/downloaders/base.py
index 3b160c6..08be4bd 100644
--- a/couchpotato/core/downloaders/base.py
+++ b/couchpotato/core/downloaders/base.py
@@ -49,7 +49,10 @@ class Downloader(Provider):
 
         return []
 
-    def _download(self, data = {}, movie = {}, manual = False, filedata = None):
+    def _download(self, data = None, movie = None, manual = False, filedata = None):
+        if not movie: movie = {}
+        if not data: data = {}
+
         if self.isDisabled(manual, data):
             return
         return self.download(data = data, movie = movie, filedata = filedata)
@@ -128,15 +131,21 @@ class Downloader(Provider):
             'id': download_id
         }
 
-    def isDisabled(self, manual = False, data = {}):
+    def isDisabled(self, manual = False, data = None):
+        if not data: data = {}
+
         return not self.isEnabled(manual, data)
 
-    def _isEnabled(self, manual, data = {}):
+    def _isEnabled(self, manual, data = None):
+        if not data: data = {}
+
         if not self.isEnabled(manual, data):
             return
         return True
 
-    def isEnabled(self, manual = False, data = {}):
+    def isEnabled(self, manual = False, data = None):
+        if not data: data = {}
+
         d_manual = self.conf('manual', default = False)
         return super(Downloader, self).isEnabled() and \
             (d_manual and manual or d_manual is False) and \
diff --git a/couchpotato/core/downloaders/blackhole/main.py b/couchpotato/core/downloaders/blackhole/main.py
index 750c6c7..9a5a621 100644
--- a/couchpotato/core/downloaders/blackhole/main.py
+++ b/couchpotato/core/downloaders/blackhole/main.py
@@ -12,7 +12,9 @@ class Blackhole(Downloader):
 
     protocol = ['nzb', 'torrent', 'torrent_magnet']
 
-    def download(self, data = {}, movie = {}, filedata = None):
+    def download(self, data = None, movie = None, filedata = None):
+        if not movie: movie = {}
+        if not data: data = {}
 
         directory = self.conf('directory')
         if not directory or not os.path.isdir(directory):
@@ -62,7 +64,8 @@ class Blackhole(Downloader):
         else:
             return ['nzb']
 
-    def isEnabled(self, manual = False, data = {}):
+    def isEnabled(self, manual = False, data = None):
+        if not data: data = {}
         for_protocol = ['both']
         if data and 'torrent' in data.get('protocol'):
             for_protocol.append('torrent')
diff --git a/couchpotato/core/downloaders/nzbget/main.py b/couchpotato/core/downloaders/nzbget/main.py
index adeedea..35d47de 100644
--- a/couchpotato/core/downloaders/nzbget/main.py
+++ b/couchpotato/core/downloaders/nzbget/main.py
@@ -19,7 +19,9 @@ class NZBGet(Downloader):
 
     url = 'http://%(username)s:%(password)s@%(host)s/xmlrpc'
 
-    def download(self, data = {}, movie = {}, filedata = None):
+    def download(self, data = None, movie = None, filedata = None):
+        if not movie: movie = {}
+        if not data: data = {}
 
         if not filedata:
             log.error('Unable to get NZB file: %s', traceback.format_exc())
diff --git a/couchpotato/core/downloaders/nzbvortex/main.py b/couchpotato/core/downloaders/nzbvortex/main.py
index 1e0a4b2..a652f11 100644
--- a/couchpotato/core/downloaders/nzbvortex/main.py
+++ b/couchpotato/core/downloaders/nzbvortex/main.py
@@ -23,7 +23,9 @@ class NZBVortex(Downloader):
     api_level = None
     session_id = None
 
-    def download(self, data = {}, movie = {}, filedata = None):
+    def download(self, data = None, movie = None, filedata = None):
+        if not movie: movie = {}
+        if not data: data = {}
 
         # Send the nzb
         try:
@@ -97,9 +99,10 @@ class NZBVortex(Downloader):
         return False
 
 
-    def call(self, call, parameters = {}, repeat = False, auth = True, *args, **kwargs):
+    def call(self, call, parameters = None, repeat = False, auth = True, *args, **kwargs):
 
         # Login first
+        if not parameters: parameters = {}
         if not self.session_id and auth:
             self.login()
 
@@ -148,7 +151,8 @@ class NZBVortex(Downloader):
 
         return self.api_level
 
-    def isEnabled(self, manual = False, data = {}):
+    def isEnabled(self, manual = False, data = None):
+        if not data: data = {}
         return super(NZBVortex, self).isEnabled(manual, data) and self.getApiLevel()
 
 
diff --git a/couchpotato/core/downloaders/pneumatic/main.py b/couchpotato/core/downloaders/pneumatic/main.py
index 25923e0..643350e 100644
--- a/couchpotato/core/downloaders/pneumatic/main.py
+++ b/couchpotato/core/downloaders/pneumatic/main.py
@@ -12,7 +12,9 @@ class Pneumatic(Downloader):
     protocol = ['nzb']
     strm_syntax = 'plugin://plugin.program.pneumatic/?mode=strm&type=add_file&nzb=%s&nzbname=%s'
 
-    def download(self, data = {}, movie = {}, filedata = None):
+    def download(self, data = None, movie = None, filedata = None):
+        if not movie: movie = {}
+        if not data: data = {}
 
         directory = self.conf('directory')
         if not directory or not os.path.isdir(directory):
diff --git a/couchpotato/core/downloaders/sabnzbd/main.py b/couchpotato/core/downloaders/sabnzbd/main.py
index 110c55b..08ee409 100644
--- a/couchpotato/core/downloaders/sabnzbd/main.py
+++ b/couchpotato/core/downloaders/sabnzbd/main.py
@@ -15,7 +15,9 @@ class Sabnzbd(Downloader):
 
     protocol = ['nzb']
 
-    def download(self, data = {}, movie = {}, filedata = None):
+    def download(self, data = None, movie = None, filedata = None):
+        if not movie: movie = {}
+        if not data: data = {}
 
         log.info('Sending "%s" to SABnzbd.', data.get('name'))
 
diff --git a/couchpotato/core/downloaders/synology/main.py b/couchpotato/core/downloaders/synology/main.py
index 58ab099..d5082c7 100644
--- a/couchpotato/core/downloaders/synology/main.py
+++ b/couchpotato/core/downloaders/synology/main.py
@@ -12,7 +12,9 @@ class Synology(Downloader):
     protocol = ['nzb', 'torrent', 'torrent_magnet']
     log = CPLog(__name__)
 
-    def download(self, data, movie, filedata = None):
+    def download(self, data = None, movie = None, filedata = None):
+        if not movie: movie = {}
+        if not data: data = {}
 
         response = False
         log.error('Sending "%s" (%s) to Synology.', (data['name'], data['protocol']))
@@ -49,7 +51,9 @@ class Synology(Downloader):
         else:
             return ['nzb']
 
-    def isEnabled(self, manual = False, data = {}):
+    def isEnabled(self, manual = False, data = None):
+        if not data: data = {}
+
         for_protocol = ['both']
         if data and 'torrent' in data.get('protocol'):
             for_protocol.append('torrent')
diff --git a/couchpotato/core/downloaders/utorrent/main.py b/couchpotato/core/downloaders/utorrent/main.py
index e1b9938..d933007 100644
--- a/couchpotato/core/downloaders/utorrent/main.py
+++ b/couchpotato/core/downloaders/utorrent/main.py
@@ -36,7 +36,9 @@ class uTorrent(Downloader):
 
         return self.utorrent_api
 
-    def download(self, data, movie, filedata = None):
+    def download(self, data = None, movie = None, filedata = None):
+        if not movie: movie = {}
+        if not data: data = {}
 
         log.debug('Sending "%s" (%s) to uTorrent.', (data.get('name'), data.get('protocol')))
 
@@ -280,7 +282,9 @@ class uTorrentAPI(object):
 
         return settings_dict
 
-    def set_settings(self, settings_dict = {}):
+    def set_settings(self, settings_dict = None):
+        if not settings_dict: settings_dict = {}
+
         for key in settings_dict:
             if isinstance(settings_dict[key], bool):
                 settings_dict[key] = 1 if settings_dict[key] else 0
diff --git a/couchpotato/core/media/_base/searcher/main.py b/couchpotato/core/media/_base/searcher/main.py
index 3222edb..89afd75 100644
--- a/couchpotato/core/media/_base/searcher/main.py
+++ b/couchpotato/core/media/_base/searcher/main.py
@@ -146,7 +146,8 @@ class Searcher(SearcherBase):
 
         return search_protocols
 
-    def containsOtherQuality(self, nzb, movie_year = None, preferred_quality = {}):
+    def containsOtherQuality(self, nzb, movie_year = None, preferred_quality = None):
+        if not preferred_quality: preferred_quality = {}
 
         name = nzb['name']
         size = nzb.get('size', 0)
diff --git a/couchpotato/core/media/movie/_base/main.py b/couchpotato/core/media/movie/_base/main.py
index a8d890d..4299f56 100644
--- a/couchpotato/core/media/movie/_base/main.py
+++ b/couchpotato/core/media/movie/_base/main.py
@@ -346,7 +346,8 @@ class MovieBase(MovieTypeBase):
             'movies': movies,
         }
 
-    def add(self, params = {}, force_readd = True, search_after = True, update_library = False, status_id = None):
+    def add(self, params = None, force_readd = True, search_after = True, update_library = False, status_id = None):
+        if not params: params = {}
 
         if not params.get('identifier'):
             msg = 'Can\'t add movie without imdb identifier.'
diff --git a/couchpotato/core/media/movie/library/movie/main.py b/couchpotato/core/media/movie/library/movie/main.py
index 12e6abc..718e739 100644
--- a/couchpotato/core/media/movie/library/movie/main.py
+++ b/couchpotato/core/media/movie/library/movie/main.py
@@ -20,7 +20,9 @@ class MovieLibraryPlugin(LibraryBase):
         addEvent('library.update.movie', self.update)
         addEvent('library.update.movie.release_date', self.updateReleaseDate)
 
-    def add(self, attrs = {}, update_after = True):
+    def add(self, attrs = None, update_after = True):
+        if not attrs: attrs = {}
+
         primary_provider = attrs.get('primary_provider', 'imdb')
 
         db = get_session()
diff --git a/couchpotato/core/notifications/base.py b/couchpotato/core/notifications/base.py
index 61cb212..4c0d099 100644
--- a/couchpotato/core/notifications/base.py
+++ b/couchpotato/core/notifications/base.py
@@ -32,7 +32,9 @@ class Notification(Provider):
                 addEvent(listener, self.createNotifyHandler(listener))
 
     def createNotifyHandler(self, listener):
-        def notify(message = None, group = {}, data = None):
+        def notify(message = None, group = None, data = None):
+            if not group: group = {}
+
             if not self.conf('on_snatch', default = True) and listener == 'movie.snatched':
                 return
             return self._notify(message = message, data = data if data else group, listener = listener)
@@ -47,8 +49,8 @@ class Notification(Provider):
             return self.notify(*args, **kwargs)
         return False
 
-    def notify(self, message = '', data = {}, listener = None):
-        pass
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
     def test(self, **kwargs):
 
diff --git a/couchpotato/core/notifications/boxcar/main.py b/couchpotato/core/notifications/boxcar/main.py
index b30d487..0fca749 100644
--- a/couchpotato/core/notifications/boxcar/main.py
+++ b/couchpotato/core/notifications/boxcar/main.py
@@ -10,7 +10,8 @@ class Boxcar(Notification):
 
     url = 'https://boxcar.io/devices/providers/7MNNXY3UIzVBwvzkKwkC/notifications'
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         try:
             message = message.strip()
diff --git a/couchpotato/core/notifications/core/main.py b/couchpotato/core/notifications/core/main.py
index 21cd197..a9a20b0 100644
--- a/couchpotato/core/notifications/core/main.py
+++ b/couchpotato/core/notifications/core/main.py
@@ -128,7 +128,8 @@ class CoreNotifier(Notification):
 
         Env.prop(prop_name, value = last_check)
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         db = get_session()
 
@@ -149,7 +150,8 @@ class CoreNotifier(Notification):
 
         return True
 
-    def frontend(self, type = 'notification', data = {}, message = None):
+    def frontend(self, type = 'notification', data = None, message = None):
+        if not data: data = {}
 
         log.debug('Notifying frontend')
 
diff --git a/couchpotato/core/notifications/email/main.py b/couchpotato/core/notifications/email/main.py
index 21fcf15..f94688d 100644
--- a/couchpotato/core/notifications/email/main.py
+++ b/couchpotato/core/notifications/email/main.py
@@ -11,7 +11,8 @@ log = CPLog(__name__)
 
 class Email(Notification):
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         # Extract all the settings from settings
         from_address = self.conf('from')
diff --git a/couchpotato/core/notifications/growl/main.py b/couchpotato/core/notifications/growl/main.py
index caad661..dabeea0 100644
--- a/couchpotato/core/notifications/growl/main.py
+++ b/couchpotato/core/notifications/growl/main.py
@@ -43,7 +43,8 @@ class Growl(Notification):
             else:
                 log.error('Failed register of growl: %s', traceback.format_exc())
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         self.register()
 
diff --git a/couchpotato/core/notifications/nmj/main.py b/couchpotato/core/notifications/nmj/main.py
index 43bb950..1479fb1 100644
--- a/couchpotato/core/notifications/nmj/main.py
+++ b/couchpotato/core/notifications/nmj/main.py
@@ -64,8 +64,9 @@ class NMJ(Notification):
             'mount': mount,
         }
 
-    def addToLibrary(self, message = None, group = {}):
+    def addToLibrary(self, message = None, group = None):
         if self.isDisabled(): return
+        if not group: group = {}
 
         host = self.conf('host')
         mount = self.conf('mount')
diff --git a/couchpotato/core/notifications/notifo/main.py b/couchpotato/core/notifications/notifo/main.py
index 6e4d7ad..2d56ed7 100644
--- a/couchpotato/core/notifications/notifo/main.py
+++ b/couchpotato/core/notifications/notifo/main.py
@@ -12,7 +12,8 @@ class Notifo(Notification):
 
     url = 'https://api.notifo.com/v1/send_notification'
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         try:
             params = {
diff --git a/couchpotato/core/notifications/notifymyandroid/main.py b/couchpotato/core/notifications/notifymyandroid/main.py
index 5e5bfb9..92e5956 100644
--- a/couchpotato/core/notifications/notifymyandroid/main.py
+++ b/couchpotato/core/notifications/notifymyandroid/main.py
@@ -8,7 +8,8 @@ log = CPLog(__name__)
 
 class NotifyMyAndroid(Notification):
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         nma = pynma.PyNMA()
         keys = splitString(self.conf('api_key'))
diff --git a/couchpotato/core/notifications/plex/main.py b/couchpotato/core/notifications/plex/main.py
index 9becfb5..f6088f5 100644
--- a/couchpotato/core/notifications/plex/main.py
+++ b/couchpotato/core/notifications/plex/main.py
@@ -17,8 +17,9 @@ class Plex(Notification):
         super(Plex, self).__init__()
         addEvent('renamer.after', self.addToLibrary)
 
-    def addToLibrary(self, message = None, group = {}):
+    def addToLibrary(self, message = None, group = None):
         if self.isDisabled(): return
+        if not group: group = {}
 
         log.info('Sending notification to Plex')
         hosts = self.getHosts(port = 32400)
@@ -45,7 +46,8 @@ class Plex(Notification):
 
         return True
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         hosts = self.getHosts(port = 3000)
         successful = 0
diff --git a/couchpotato/core/notifications/prowl/main.py b/couchpotato/core/notifications/prowl/main.py
index e5c4678..a8a3dda 100644
--- a/couchpotato/core/notifications/prowl/main.py
+++ b/couchpotato/core/notifications/prowl/main.py
@@ -12,7 +12,8 @@ class Prowl(Notification):
         'api': 'https://api.prowlapp.com/publicapi/add'
     }
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         data = {
             'apikey': self.conf('api_key'),
diff --git a/couchpotato/core/notifications/pushalot/main.py b/couchpotato/core/notifications/pushalot/main.py
index 4c5e76c..4e3b6e7 100644
--- a/couchpotato/core/notifications/pushalot/main.py
+++ b/couchpotato/core/notifications/pushalot/main.py
@@ -11,7 +11,8 @@ class Pushalot(Notification):
         'api': 'https://pushalot.com/api/sendmessage'
     }
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         data = {
             'AuthorizationToken': self.conf('auth_token'),
diff --git a/couchpotato/core/notifications/pushover/main.py b/couchpotato/core/notifications/pushover/main.py
index ea5e774..76f730b 100644
--- a/couchpotato/core/notifications/pushover/main.py
+++ b/couchpotato/core/notifications/pushover/main.py
@@ -11,7 +11,8 @@ class Pushover(Notification):
 
     app_token = 'YkxHMYDZp285L265L3IwH3LmzkTaCy'
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         http_handler = HTTPSConnection("api.pushover.net:443")
 
diff --git a/couchpotato/core/notifications/synoindex/main.py b/couchpotato/core/notifications/synoindex/main.py
index 3980430..0f7775d 100644
--- a/couchpotato/core/notifications/synoindex/main.py
+++ b/couchpotato/core/notifications/synoindex/main.py
@@ -15,8 +15,9 @@ class Synoindex(Notification):
         super(Synoindex, self).__init__()
         addEvent('renamer.after', self.addToLibrary)
 
-    def addToLibrary(self, message = None, group = {}):
+    def addToLibrary(self, message = None, group = None):
         if self.isDisabled(): return
+        if not group: group = {}
 
         command = [self.index_path, '-A', group.get('destination_dir')]
         log.info('Executing synoindex command: %s ', command)
diff --git a/couchpotato/core/notifications/toasty/main.py b/couchpotato/core/notifications/toasty/main.py
index 79b021e..c65b6b4 100644
--- a/couchpotato/core/notifications/toasty/main.py
+++ b/couchpotato/core/notifications/toasty/main.py
@@ -11,7 +11,8 @@ class Toasty(Notification):
         'api': 'http://api.supertoasty.com/notify/%s?%s'
     }
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         data = {
             'title': self.default_title,
diff --git a/couchpotato/core/notifications/trakt/main.py b/couchpotato/core/notifications/trakt/main.py
index 86d4708..99d5553 100644
--- a/couchpotato/core/notifications/trakt/main.py
+++ b/couchpotato/core/notifications/trakt/main.py
@@ -13,7 +13,8 @@ class Trakt(Notification):
 
     listen_to = ['movie.downloaded']
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         post_data = {
             'username': self.conf('automation_username'),
diff --git a/couchpotato/core/notifications/twitter/main.py b/couchpotato/core/notifications/twitter/main.py
index 4a34d60..ad4fc31 100644
--- a/couchpotato/core/notifications/twitter/main.py
+++ b/couchpotato/core/notifications/twitter/main.py
@@ -30,7 +30,8 @@ class Twitter(Notification):
         addApiView('notify.%s.auth_url' % self.getName().lower(), self.getAuthorizationUrl)
         addApiView('notify.%s.credentials' % self.getName().lower(), self.getCredentials)
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         api = Api(self.consumer_key, self.consumer_secret, self.conf('access_token_key'), self.conf('access_token_secret'))
 
diff --git a/couchpotato/core/notifications/xbmc/main.py b/couchpotato/core/notifications/xbmc/main.py
index 836b40c..dc185c4 100755
--- a/couchpotato/core/notifications/xbmc/main.py
+++ b/couchpotato/core/notifications/xbmc/main.py
@@ -17,7 +17,8 @@ class XBMC(Notification):
     use_json_notifications = {}
     http_time_between_calls = 0
 
-    def notify(self, message = '', data = {}, listener = None):
+    def notify(self, message = '', data = None, listener = None):
+        if not data: data = {}
 
         hosts = splitString(self.conf('host'))
 
diff --git a/couchpotato/core/plugins/file/main.py b/couchpotato/core/plugins/file/main.py
index cdd67f5..2f458f7 100644
--- a/couchpotato/core/plugins/file/main.py
+++ b/couchpotato/core/plugins/file/main.py
@@ -83,7 +83,8 @@ class FileManager(Plugin):
         Env.get('app').add_handlers(".*$", [('%s%s' % (Env.get('api_base'), route), StaticFileHandler, {'path': Env.get('cache_dir')})])
 
 
-    def download(self, url = '', dest = None, overwrite = False, urlopen_kwargs = {}):
+    def download(self, url = '', dest = None, overwrite = False, urlopen_kwargs = None):
+        if not urlopen_kwargs: urlopen_kwargs = {}
 
         if not dest: # to Cache
             dest = os.path.join(Env.get('cache_dir'), '%s.%s' % (md5(url), getExt(url)))
@@ -100,7 +101,9 @@ class FileManager(Plugin):
         self.createFile(dest, filedata, binary = True)
         return dest
 
-    def add(self, path = '', part = 1, type_tuple = (), available = 1, properties = {}):
+    def add(self, path = '', part = 1, type_tuple = (), available = 1, properties = None):
+        if not properties: properties = {}
+
         type_id = self.getType(type_tuple).get('id')
         db = get_session()
 
diff --git a/couchpotato/core/plugins/manage/main.py b/couchpotato/core/plugins/manage/main.py
index f1ffefa..3a475b7 100644
--- a/couchpotato/core/plugins/manage/main.py
+++ b/couchpotato/core/plugins/manage/main.py
@@ -26,7 +26,8 @@ class Manage(Plugin):
         addEvent('manage.diskspace', self.getDiskSpace)
 
         # Add files after renaming
-        def after_rename(message = None, group = {}):
+        def after_rename(message = None, group = None):
+            if not group: group = {}
             return self.scanFilesToLibrary(folder = group['destination_dir'], files = group['renamed_files'])
         addEvent('renamer.after', after_rename, priority = 110)
 
@@ -168,7 +169,9 @@ class Manage(Plugin):
         fireEvent('notify.frontend', type = 'manage.updating', data = False)
         self.in_progress = False
 
-    def createAddToLibrary(self, folder, added_identifiers = []):
+    def createAddToLibrary(self, folder, added_identifiers = None):
+        if not added_identifiers: added_identifiers = []
+
         def addToLibrary(group, total_found, to_go):
             if self.in_progress[folder]['total'] is None:
                 self.in_progress[folder] = {
diff --git a/couchpotato/core/plugins/quality/main.py b/couchpotato/core/plugins/quality/main.py
index 0e67a07..15710a8 100644
--- a/couchpotato/core/plugins/quality/main.py
+++ b/couchpotato/core/plugins/quality/main.py
@@ -152,7 +152,8 @@ class QualityPlugin(Plugin):
 
         return True
 
-    def guess(self, files, extra = {}):
+    def guess(self, files, extra = None):
+        if not extra: extra = {}
 
         # Create hash for cache
         hash = md5(str([f.replace('.' + getExt(f), '') for f in files]))
diff --git a/couchpotato/core/plugins/renamer/main.py b/couchpotato/core/plugins/renamer/main.py
index a45a265..4bbf351 100644
--- a/couchpotato/core/plugins/renamer/main.py
+++ b/couchpotato/core/plugins/renamer/main.py
@@ -495,7 +495,9 @@ class Renamer(Plugin):
 
         self.renaming_started = False
 
-    def getRenameExtras(self, extra_type = '', replacements = {}, folder_name = '', file_name = '', destination = '', group = {}, current_file = '', remove_multiple = False):
+    def getRenameExtras(self, extra_type = '', replacements = None, folder_name = '', file_name = '', destination = '', group = None, current_file = '', remove_multiple = False):
+        if not group: group = {}
+        if not replacements: replacements = {}
 
         replacements = replacements.copy()
         rename_files = {}
@@ -843,11 +845,12 @@ Remove it if you want it to be renamed (again, or at least let it try again)
 
     def statusInfoComplete(self, item):
         return item['id'] and item['downloader'] and item['folder']
-    
+
     def movieInFromFolder(self, movie_folder):
         return movie_folder and self.conf('from') in movie_folder or not movie_folder
 
-    def extractFiles(self, folder = None, movie_folder = None, files = [], cleanup = False):
+    def extractFiles(self, folder = None, movie_folder = None, files = None, cleanup = False):
+        if not files: files = []
 
         # RegEx for finding rar files
         archive_regex = '(?P<file>^(?P<base>(?:(?!\.part\d+\.rar$).)*)\.(?:(?:part0*1\.)?rar)$)'
@@ -941,7 +944,7 @@ Remove it if you want it to be renamed (again, or at least let it try again)
                     self.makeDir(os.path.dirname(move_to))
                     self.moveFile(leftoverfile, move_to, cleanup)
                 except Exception, e:
-                    log.error('Failed moving left over file %s to %s: %s %s',(leftoverfile, move_to, e, traceback.format_exc()))
+                    log.error('Failed moving left over file %s to %s: %s %s', (leftoverfile, move_to, e, traceback.format_exc()))
                     # As we probably tried to overwrite the nfo file, check if it exists and then remove the original
                     if os.path.isfile(move_to):
                         if cleanup:
@@ -964,7 +967,7 @@ Remove it if you want it to be renamed (again, or at least let it try again)
         if extr_files:
             files.extend(extr_files)
 
-        # Cleanup files and folder if movie_folder was not provided 
+        # Cleanup files and folder if movie_folder was not provided
         if not movie_folder:
             files = []
             folder = None
diff --git a/couchpotato/core/plugins/subtitle/main.py b/couchpotato/core/plugins/subtitle/main.py
index 2aa22f4..e447dac 100644
--- a/couchpotato/core/plugins/subtitle/main.py
+++ b/couchpotato/core/plugins/subtitle/main.py
@@ -42,7 +42,6 @@ class Subtitle(Plugin):
                     subliminal.list_subtitles(files, cache_dir = Env.get('cache_dir'), multi = True, languages = self.getLanguages(), services = self.services)
 
     def searchSingle(self, group):
-
         if self.isDisabled(): return
 
         try:
diff --git a/couchpotato/core/plugins/trailer/main.py b/couchpotato/core/plugins/trailer/main.py
index 1a8955f..e27e3f9 100644
--- a/couchpotato/core/plugins/trailer/main.py
+++ b/couchpotato/core/plugins/trailer/main.py
@@ -12,8 +12,8 @@ class Trailer(Plugin):
     def __init__(self):
         addEvent('renamer.after', self.searchSingle)
 
-    def searchSingle(self, message = None, group = {}):
-
+    def searchSingle(self, message = None, group = None):
+        if not group: group = {}
         if self.isDisabled() or len(group['files']['trailer']) > 0: return
 
         trailers = fireEvent('trailer.search', group = group, merge = True)
@@ -40,4 +40,3 @@ class Trailer(Plugin):
             break
 
         return True
-
diff --git a/couchpotato/core/providers/info/couchpotatoapi/main.py b/couchpotato/core/providers/info/couchpotatoapi/main.py
index cdbc513..ef7db1f 100644
--- a/couchpotato/core/providers/info/couchpotatoapi/main.py
+++ b/couchpotato/core/providers/info/couchpotatoapi/main.py
@@ -80,7 +80,10 @@ class CouchPotatoApi(MovieProvider):
 
         return dates
 
-    def getSuggestions(self, movies = [], ignore = []):
+    def getSuggestions(self, movies = None, ignore = None):
+        if not ignore: ignore = []
+        if not movies: movies = []
+
         suggestions = self.getJsonData(self.urls['suggest'], params = {
             'movies': ','.join(movies),
             'ignore': ','.join(ignore),
diff --git a/couchpotato/core/providers/metadata/base.py b/couchpotato/core/providers/metadata/base.py
index 7a65568..f561003 100644
--- a/couchpotato/core/providers/metadata/base.py
+++ b/couchpotato/core/providers/metadata/base.py
@@ -17,8 +17,9 @@ class MetaDataBase(Plugin):
     def __init__(self):
         addEvent('renamer.after', self.create)
 
-    def create(self, message = None, group = {}):
+    def create(self, message = None, group = None):
         if self.isDisabled(): return
+        if not group: group = {}
 
         log.info('Creating %s metadata.', self.getName())
 
@@ -65,7 +66,8 @@ class MetaDataBase(Plugin):
             except:
                 log.error('Unable to create %s file: %s', (file_type, traceback.format_exc()))
 
-    def getRootName(self, data = {}):
+    def getRootName(self, data = None):
+        if not data: data = {}
         return os.path.join(data['destination_dir'], data['filename'])
 
     def getFanartName(self, name, root):
@@ -77,10 +79,13 @@ class MetaDataBase(Plugin):
     def getNfoName(self, name, root):
         return
 
-    def getNfo(self, movie_info = {}, data = {}):
-        return
+    def getNfo(self, movie_info = None, data = None):
+        if not data: data = {}
+        if not movie_info: movie_info = {}
 
-    def getThumbnail(self, movie_info = {}, data = {}, wanted_file_type = 'poster_original'):
+    def getThumbnail(self, movie_info = None, data = None, wanted_file_type = 'poster_original'):
+        if not data: data = {}
+        if not movie_info: movie_info = {}
         file_types = fireEvent('file.types', single = True)
         file_type = {}
 
@@ -102,5 +107,7 @@ class MetaDataBase(Plugin):
         except:
             pass
 
-    def getFanart(self, movie_info = {}, data = {}):
+    def getFanart(self, movie_info = None, data = None):
+        if not data: data = {}
+        if not movie_info: movie_info = {}
         return self.getThumbnail(movie_info = movie_info, data = data, wanted_file_type = 'backdrop_original')
diff --git a/couchpotato/core/providers/metadata/xbmc/main.py b/couchpotato/core/providers/metadata/xbmc/main.py
index 820df15..e865e2d 100644
--- a/couchpotato/core/providers/metadata/xbmc/main.py
+++ b/couchpotato/core/providers/metadata/xbmc/main.py
@@ -24,7 +24,9 @@ class XBMC(MetaDataBase):
     def createMetaName(self, basename, name, root):
         return os.path.join(root, basename.replace('%s', name))
 
-    def getNfo(self, movie_info = {}, data = {}):
+    def getNfo(self, movie_info = None, data = None):
+        if not data: data = {}
+        if not movie_info: movie_info = {}
 
         # return imdb url only
         if self.conf('meta_url_only'):
diff --git a/couchpotato/core/settings/__init__.py b/couchpotato/core/settings/__init__.py
index b75e5dd..61d982f 100644
--- a/couchpotato/core/settings/__init__.py
+++ b/couchpotato/core/settings/__init__.py
@@ -72,7 +72,9 @@ class Settings(object):
         addEvent('settings.register', self.registerDefaults)
         addEvent('settings.save', self.save)
 
-    def registerDefaults(self, section_name, options = {}, save = True):
+    def registerDefaults(self, section_name, options = None, save = True):
+        if not options: options = {}
+
         self.addSection(section_name)
 
         for option_name, option in options.iteritems():
diff --git a/couchpotato/core/settings/model.py b/couchpotato/core/settings/model.py
index 2737392..f39544b 100644
--- a/couchpotato/core/settings/model.py
+++ b/couchpotato/core/settings/model.py
@@ -137,7 +137,10 @@ class Release(Entity):
     files = ManyToMany('File')
     info = OneToMany('ReleaseInfo', cascade = 'all, delete-orphan')
 
-    def to_dict(self, deep = {}, exclude = []):
+    def to_dict(self, deep = None, exclude = None):
+        if not exclude: exclude = []
+        if not deep: deep = {}
+
         orig_dict = super(Release, self).to_dict(deep = deep, exclude = exclude)
 
         new_info = {}
@@ -200,7 +203,10 @@ class Profile(Entity):
     movie = OneToMany('Movie')
     types = OneToMany('ProfileType', cascade = 'all, delete-orphan')
 
-    def to_dict(self, deep = {}, exclude = []):
+    def to_dict(self, deep = None, exclude = None):
+        if not exclude: exclude = []
+        if not deep: deep = {}
+
         orig_dict = super(Profile, self).to_dict(deep = deep, exclude = exclude)
         orig_dict['core'] = orig_dict.get('core') or False
         orig_dict['hide'] = orig_dict.get('hide') or False