removed mutable as parameters

openlp/core/lib/ui.py

@@ -67,7 +67,7 @@ def add_welcome_page(parent, image):
     parent.addPage(parent.welcomePage)
 
 
-def create_button_box(dialog, name, standard_buttons, custom_buttons=[]):
+def create_button_box(dialog, name, standard_buttons, custom_buttons=None):
     """
     Creates a QDialogButtonBox with the given buttons. The ``accepted()`` and
     ``rejected()`` signals of the button box are connected with the dialogs
@@ -88,6 +88,8 @@ def create_button_box(dialog, name, standard_buttons, custom_buttons=[]):
         QtGui.QAbstractButton it is added with QDialogButtonBox.ActionRole.
         Otherwhise the item has to be a tuple of a button and a ButtonRole.
     """
+    if custom_buttons is None:
+        custom_buttons = []
     buttons = QtGui.QDialogButtonBox.NoButton
     if u'ok' in standard_buttons:
         buttons |= QtGui.QDialogButtonBox.Ok

openlp/plugins/remotes/lib/httpserver.py

@@ -138,7 +138,9 @@ class HttpResponse(object):
         'Content-Type': 'text/html; charset="utf-8"\r\n'
     }
 
-    def __init__(self, content='', headers={}, code=None):
+    def __init__(self, content='', headers=None, code=None):
+        if headers is None:
+            headers = {}
         self.content = content
         for key, value in headers.iteritems():
             self.headers[key] = value

openlp/plugins/songs/lib/sundayplusimport.py

@@ -121,7 +121,7 @@ class SundayPlusImport(SongImport):
                         end = data.find(')', i) + 1
                     value = data[i:end]
                 # If we are in the main group.
-                if cell == False:
+                if not cell:
                     if name == 'title':
                         self.title = self.decode(self.unescape(value))
                     elif name == 'Author':