python - Why not constructor of super class invoked when we declare the object of sub class? -


i java programmer, beginner in python programming. have noticed unexpected behavior in python programming. expecting print sequence b class ,a class constructors. it's executing constructor of only.

output "its constructor of a",could please me understand flow of execution. in advance

class b:     def __init__(self):         print 'its constructor of b'      class a(b):     def __init__(self):         print 'its constructor of a'         #b.__init__(self)  if __name__=='__main__':     obj=a()

in python should call parent's initializer (that's how __init__ method called, - "constructor" else) explicitly.

you can did in commented out line. better yet, should use super function, figures out, parent access you. works new-style classes though (basically, means, root of class hierarchy must inherit object).


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