class Contact(DictMixin):

  def __init__ (self, name,parent=const.modelRootNode, avatar=None):
...
    
    self.children=[]
    self.parent=parent
    
    if self.parent != const.modelRootNode :
      self.parent.children.sort(lambda x,y: cmp(x["name"],y["name"]))
      
  def getParent(self):
    return self.parent
...


contacts.append( Contact(name="User 1",parent=notInListGr,avatar="resources/av1.png" ) )

получаю на выходе 


~/crabim> python main.py                                                          
PyQt4.QtCore.QPoint(1279, 992)                                                                   
Traceback (most recent call last):                                                               
  File "main.py", line 91, in <module>                                                           
    main()                                                                                       
  File "main.py", line 69, in main                                                               
    contacts = ContactDB() #in future: c contactDB(settings.getContactDBfilename())
  File "/home/fermer/crabim/modules/contacts.py", line 26, in __init__
    self.contacts.append( Contact(name="User 1",parent=notInListGr,avatar="resources/av1.png" ) )
  File "/home/fermer/crabim/modules/contacts.py", line 61, in __init__
    if self.parent != const.modelRootNode :
  File "/usr/lib64/python2.6/UserDict.py", line 177, in __cmp__
    return cmp(dict(self.iteritems()), other)
  File "/usr/lib64/python2.6/UserDict.py", line 109, in iteritems
    for k in self:
  File "/usr/lib64/python2.6/UserDict.py", line 96, in __iter__
    for k in self.keys():
TypeError: keys() takes no arguments (1 given)