Category: Python
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Python multiple inheritance: How super() follows the MRO
Python class C inherits from (A, B), and both A.__init__ and B.__init__ invoke super().__init__(). We run C(). It prints “B, A”. How does B.__init__ run? A doesn’t inherit from B. The answer: super() looks at the MRO of C, not A. B isn’t in A.__mro__. But it is in C.__mro__.
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Python multiple inheritance: Why every class needs super()
Multiple inheritance in Python? Make sure all parents run super():
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Python multiple inheritance: Which __init__ actually runs
In a Python child class with two parents, which __init__ runs?
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Python multiple inheritance: Listing parents with __bases__
Does Python allow for multiple inheritance? Yes: And so: C.__bases__ returns: (<class ‘__main__.A’>, <class ‘__main__.B’>)
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Python super() and the MRO: How method lookup climbs the hierarchy
In Python, super() searches the MRO until it finds a match:
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Python inheritance: Skipping super().__init__ loses parent attributes
Didn’t call super() __init__ in your Python class? Attributes normally set on the parent won’t be on the child!
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Python super().__init__: Passing arguments to the parent class
The most common place we use super() in Python? __init__:
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Python super(): Misspelled method names raise AttributeError
Misspelled the method you invoke via super() in a Python method? It’s a runtime error: We get: AttributeError: ‘super’ object has no attribute ‘y’
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Python’s super(): A proxy for calling parent-class methods
A Python method can invoke a method in the parent class with super(): super() doesn’t invoke the method. It’s a proxy on which you invoke the method you want.
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Python method overriding: Child methods replace the parent’s
If a Python subclass defines a method with the same name as the parent, the parent’s method isn’t invoked: