Python New class inheritance Order

Inheritance Order

Breadth First principle:

classA:PassclassB (A):PassclassC (A):PassclassD (B):PassclassE (C):PassclassF (D, E):PassPrint("f.__mro__ ="F.__mro__)Print("F.mro () =", F.mro ())

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Principles of inheritance

How Python actually implements inheritance:

• For each class defined, Python calculates a list of method resolution orders (MRO), which is a simple linear sequential list of all base classes.
• To implement inheritance, Python finds the base class from left to right on the MRO list until the first class that matches the property is found.
• The construction of the MRO list is implemented by a C3 linearization algorithm. We're not going to delve into the math of this algorithm, it's actually merging all of the parent's MRO lists and following three guidelines:

1. Subclasses are checked before the parent class.
2. Multiple parent classes are checked according to their order in the list.
3. If there are two legitimate choices for the next class, select the first parent class.

Python New class inheritance Order