# What's wrong in the code? # A: No call to parent __init__. To call, uncomment the code class A: def __init__(self): self._greeting = 'hello' def greet(self): print self._greeting class B(A): def __init__(self): # A.__init__(self) self._greeting_add = ', world' def greet(self): print self._greeting + self._greeting_add # No _greeting because of b = B() b.greet()