439. What is the output of the following code? class A(object): def __init__(self): print 'Constructor A was called' class B(A): def __init__(self): print "Constructor B was called" class C(B): def __init__(self): super(C,self).__init__() print 'Constructor C was called' class D(C): def __init__(self): super(D,self).__init__() print 'Constructor D was called' d = D()