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super() – basic functionality

  • reference parent class ‚dynamically‘ instead of hard-coding it
  • no need to call the name of the base class explicitly
  • working with multiple inheritance

What super() can do: advantages

  • simplyfies the use of your code by others
  • may simply writing code by unnecessity of calling parent class explicitly
  • less vulnerably to code changes
    • for example when name of base class gets changed – super method in child class will still work without changes

super() with multiple inheritance (example)

class Animal:
  def __init__(self, Animal):
    print(Animal, 'is an animal.');

class Mammal(Animal):
  def __init__(self, mammalName):
    print(mammalName, 'is a warm-blooded animal.')
    super().__init__(mammalName)

class NonWingedMammal(Mammal):
  def __init__(self, NonWingedMammal):
    print(NonWingedMammal, "can't fly.")
    super().__init__(NonWingedMammal)

class NonMarineMammal(Mammal):
  def __init__(self, NonMarineMammal):
    print(NonMarineMammal, "can't swim.")
    super().__init__(NonMarineMammal)

class Dog(NonMarineMammal, NonWingedMammal):
  def __init__(self):
    print('Dog has 4 legs.');
    super().__init__('Dog')

d = Dog()
print('')
bat = NonMarineMammal('Bat')

output

Dog has 4 legs.
Dog can't swim.
Dog can't fly.
Dog is a warm-blooded animal.
Dog is an animal.

Bat can't swim.
Bat is a warm-blooded animal.
Bat is an animal.

Method Resolution Order (MRO)

  • speficies in which order the related classed and objects are called
  • called using: Class.__mro__
>>> Dog.__mro__
(<class 'Dog'>, 
<class 'NonMarineMammal'>, 
<class 'NonWingedMammal'>, 
<class 'Mammal'>, 
<class 'Animal'>, 
<class 'object'>)

featured image by: @Quinoal (Twitter)