Abstract Base Class Python Init

According to python docs this module provides abstract base classes that can be used to test whether a class provides a particular interface.

Abstract base class python init. Python does not have abstract classes by default but it has a module or library which forms the base for defining abstract base classes abc and that module name is called abc. Though it bears some similarities to metapathfinder pathentryfinder is meant for use only within the path based import subsystem provided by pathfinder. Abc works by decorating methods of the base class as abstract and then registering concrete classes as implementations of the abstract base. An abstract method is a method that is declared but contains no implementation.

From abc import abc abstractmethod class abstractclassexample abc. For example pythons built in property does the equivalent of. Abstract base classes in python abc python server side programming programming a class is called an abstract class if it contains one or more abstract methods. In order to correctly interoperate with the abstract base class machinery the descriptor must identify itself as abstract using isabstractmethod.

For example whether it is hashable or whether it is a mapping. The following python code uses the abc module and defines an abstract base class. By default python does not provide abstract classes. New in version 33.

Here i want to call the init function of the base class. Because the square and rectangleinit methods are so similar you can simply call the superclasss init method rectangleinit from that of square by using superthis sets the length and width attributes even though you just had to supply a single length parameter to the square constructor. In general this attribute should be true if any of the methods used to compose the descriptor are abstract. It marks the method of the base class as the abstract base class and then produces concrete classes as implementations of the abstract base.

Def init self value. Value value super. This abc is a subclass of finder for compatibility reasons only. An abstract base class representing a path entry finder.

Init atabstractmethod def dosomething self. In this example rectangle is the superclass and square is the subclass.