Python inheritance

demo.py

class A:
    a_attribute = 'A attribute'
    common_attribute = 'common_attribute A'
    overriden_attribute = 'overridden_attribute of A'

    def common_method(self):
        print('  - calling A.common_method')
        return f'A.common_method. common_attribute={self.common_attribute}'

    def a_method(self):
        print('  - calling A.a_method')
        return 'A.a_method'

    def overridden_method(self):
        print('  - calling A.overridden_method')
        return 'A.overridden_method'


class B:
    b_attribute = 'B attribute'
    common_attribute = 'common_attribute B'
    overriden_attribute = 'overridden_attribute of B'

    def b_method(self):
        print('  - calling B.b_method')
        return 'B.b_method'

    def common_method(self):
        print('  - calling B.common_method')
        return f'B.common_method. common_attribute={self.common_attribute}'

    def overridden_method(self):
        print('  - calling B.overridden_method')
        return 'B.overridden_method'


class AB(A, B):
    ab_attribute = 'AB attribute'
    overriden_attribute = 'overridden_attribute of AB'

    def ab_method(self):
        print('  - calling AB.ab_method')
        return 'AB.ab_method'

    def overridden_method(self):
        print('  - calling AB.overridden_method')
        return 'AB.overridden_method'

    def super_common_method(self):
        return super().common_method()

    def super_controlled_method(self):
        self.common_attribute = 'AB overwrote this'
        return B.common_method(self)


class BA(B, A):
    ba_attribute = 'BA attribute'
    overriden_attribute = 'overridden_attribute of BA'

    def ba_method(self):
        print('  - calling BA.ab_method')
        return 'BA.ab_method'

    def overridden_method(self):
        print('  - calling BA.overridden_method')
        return 'BA.overridden_method'

    def super_common_method(self):
        return super().common_method()

    def super_controlled_method(self):
        self.common_attribute = 'BA overwrote this'
        return A.common_method(self)


def test():
    methods = [
        'common_method',
        'a_method',
        'overridden_method',
        'b_method',
        'ab_method',
        'ba_method',
        'super_common_method',
        'super_controlled_method',
    ]

    attributes = [
        'a_attribute',
        'common_attribute',
        'overriden_attribute',
        'b_attribute',
        'ab_attribute',
        'ba_attribute',
    ]

    classes = [
        AB, BA, A, B
    ]

    for c in classes:
        classname = c.__name__
        instance = c()
        print(f'\n')
        for attr in attributes:
            print(f'{classname}.{attr}: {getattr(instance, attr, None)}')

        for attr in methods:
            method = getattr(instance, attr, None)
            print(f'{classname}.{attr}: {method and method()}')

"""RESULT

AB.a_attribute: A attribute
AB.common_attribute: common_attribute A
AB.overriden_attribute: overridden_attribute of AB
AB.b_attribute: B attribute
AB.ab_attribute: AB attribute
AB.ba_attribute: None
  - calling A.common_method
AB.common_method: A.common_method. common_attribute=common_attribute A
  - calling A.a_method
AB.a_method: A.a_method
  - calling AB.overridden_method
AB.overridden_method: AB.overridden_method
  - calling B.b_method
AB.b_method: B.b_method
  - calling AB.ab_method
AB.ab_method: AB.ab_method
AB.ba_method: None
  - calling A.common_method
AB.super_common_method: A.common_method. common_attribute=common_attribute A
  - calling B.common_method
AB.super_controlled_method: B.common_method. common_attribute=AB overwrote this


BA.a_attribute: A attribute
BA.common_attribute: common_attribute B
BA.overriden_attribute: overridden_attribute of BA
BA.b_attribute: B attribute
BA.ab_attribute: None
BA.ba_attribute: BA attribute
  - calling B.common_method
BA.common_method: B.common_method. common_attribute=common_attribute B
  - calling A.a_method
BA.a_method: A.a_method
  - calling BA.overridden_method
BA.overridden_method: BA.overridden_method
  - calling B.b_method
BA.b_method: B.b_method
BA.ab_method: None
  - calling BA.ab_method
BA.ba_method: BA.ab_method
  - calling B.common_method
BA.super_common_method: B.common_method. common_attribute=common_attribute B
  - calling A.common_method
BA.super_controlled_method: A.common_method. common_attribute=BA overwrote this


A.a_attribute: A attribute
A.common_attribute: common_attribute A
A.overriden_attribute: overridden_attribute of A
A.b_attribute: None
A.ab_attribute: None
A.ba_attribute: None
  - calling A.common_method
A.common_method: A.common_method. common_attribute=common_attribute A
  - calling A.a_method
A.a_method: A.a_method
  - calling A.overridden_method
A.overridden_method: A.overridden_method
A.b_method: None
A.ab_method: None
A.ba_method: None
A.super_common_method: None
A.super_controlled_method: None


B.a_attribute: None
B.common_attribute: common_attribute B
B.overriden_attribute: overridden_attribute of B
B.b_attribute: B attribute
B.ab_attribute: None
B.ba_attribute: None
  - calling B.common_method
B.common_method: B.common_method. common_attribute=common_attribute B
B.a_method: None
  - calling B.overridden_method
B.overridden_method: B.overridden_method
  - calling B.b_method
B.b_method: B.b_method
B.ab_method: None
B.ba_method: None
B.super_common_method: None
B.super_controlled_method: None
"""