Python: Inherit the superclass __init__

python inheritance constructor init
Adam Matan picture Adam Matan · Jun 30, 2011 · Viewed 64.5k times · Source

I have a base class with a lot of __init__ arguments:

class BaseClass(object):
    def __init__(self, a, b, c, d, e, f, ...):
        self._a=a+b
        self._b=b if b else a
        ...

All the inheriting classes should run __init__ method of the base class.

I can write a __init__() method in each of the inheriting classes that would call the superclass __init__, but that would be a serious code duplication:

class A(BaseClass):
    def __init__(self, a, b, c, d, e, f, ...):
        super(A, self).__init__(a, b, c, d, e, f, ...)

class B(BaseClass):
    def __init__(self, a, b, c, d, e, f, ...):
        super(A, self).__init__(a, b, c, d, e, f, ...)

class C(BaseClass):
    def __init__(self, a, b, c, d, e, f, ...):
        super(A, self).__init__(a, b, c, d, e, f, ...)

...

What's the most Pythonic way to automatically call the superclass __init__?

Answer

Andreas Jung picture Andreas Jung · Jun 30, 2011 
super(SubClass, self).__init__(...)

Consider using *args and **kw if it helps solving your variable nightmare.

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