from PyQt4.QtGui import QGraphicsItem

class A(QGraphicsItem):
    def __init__(self):
        super(A, self).__init__()
        self.a = "a"
    
    def fa(self):
        return self.a

class B(object):
    def __init__(self):
        super(B, self).__init__()
        self._b = "b"
        
    def fb(self):
        return self._b
            
class C(A, B):
    def __init__(self):
        super(C, self).__init__()    
        
        
c = C()
print c.fa()
print c.fb()