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📛 NAME

abc - Abstract Base Classes (ABCs) according to PEP 3119.

🚀 Quick Reference

Use Case	Command	Description
Define an abstract base class	class MyABC(ABC):	Use ABC as base class to define an ABC.
Declare an abstract method	@abstractmethod	Decorator to mark a method as abstract.
Register a virtual subclass	MyABC.register(SomeClass)	Register an unrelated class as a virtual subclass.
Get cache token	get_cache_token()	Returns current ABC cache token for virtual subclasses.
Update abstract methods	update_abstractmethods(cls)	Recalculate set of abstract methods after modifications.

📚 MODULE REFERENCE

https://docs.python.org/3.10/library/abc.html

The following documentation is automatically generated from the Python source files. It may be incomplete, incorrect or include features that are considered implementation detail and may vary between Python implementations. When in doubt, consult the module reference at the location listed above.

📦 CLASSES

• builtins.classmethod(builtins.object) → abstractclassmethod
• builtins.object → ABC
• builtins.property(builtins.object) → abstractproperty
• builtins.staticmethod(builtins.object) → abstractstaticmethod
• builtins.type(builtins.object) → ABCMeta

📦 class ABC(builtins.object)

Helper class that provides a standard way to create an ABC using inheritance.

Data and other attributes defined here:

• __abstractmethods__ = frozenset()

📦 class ABCMeta(builtins.type)

Metaclass for defining Abstract Base Classes (ABCs).

Use this metaclass to create an ABC. An ABC can be subclassed directly, and then acts as a mix-in class. You can also register unrelated concrete classes (even built-in classes) and unrelated ABCs as 'virtual subclasses' — these and their descendants will be considered subclasses of the registering ABC by the built-in issubclass() function, but the registering ABC won't show up in their MRO (Method Resolution Order) nor will method implementations defined by the registering ABC be callable (not even via super()).

Method resolution order:

• ABCMeta
• builtins.type
• builtins.object

Methods defined here:

• __instancecheck__(cls, instance) — Override for isinstance(instance, cls).
• __subclasscheck__(cls, subclass) — Override for issubclass(subclass, cls).
• register(cls, subclass) — Register a virtual subclass of an ABC. Returns the subclass, to allow usage as a class decorator.

Static methods defined here:

• __new__(mcls, name, bases, namespace, **kwargs) — Create and return a new object. See help(type) for accurate signature.

Data and other attributes defined here:

• __annotations__ = {}

Methods inherited from builtins.type:

• __call__(self, /, *args, **kwargs) — Call self as a function.
• __delattr__(self, name, /) — Implement delattr(self, name).
• __dir__(self, /) — Specialized __dir__ implementation for types.
• __getattribute__(self, name, /) — Return getattr(self, name).
• __init__(self, /, *args, **kwargs) — Initialize self. See help(type(self)) for accurate signature.
• __or__(self, value, /) — Return self|value.
• __repr__(self, /) — Return repr(self).
• __ror__(self, value, /) — Return value|self.
• __setattr__(self, name, value, /) — Implement setattr(self, name, value).
• __sizeof__(self, /) — Return memory consumption of the type object.
• __subclasses__(self, /) — Return a list of immediate subclasses.
• mro(self, /) — Return a type's method resolution order.

Class methods inherited from builtins.type:

• __prepare__(...) from builtins.type — __prepare__() -> dict: used to create the namespace for the class statement

Data descriptors inherited from builtins.type:

• __abstractmethods__
• __dict__
• __text_signature__

Data and other attributes inherited from builtins.type:

• __base__ = <class 'type'> — type(object) -> the object's type, type(name, bases, dict, **kwds) -> a new type
• __bases__ = (<class 'type'>,)
• __basicsize__ = 888
• __dictoffset__ = 264
• __flags__ = 2148029952
• __itemsize__ = 40
• __mro__ = (<class 'abc.ABCMeta'>, <class 'type'>, <class 'object'>)
• __weakrefoffset__ = 368

📦 class abstractclassmethod(builtins.classmethod)

A decorator indicating abstract classmethods.

Deprecated, use 'classmethod' with 'abstractmethod' instead:

class C(ABC):
    @classmethod
    @abstractmethod
    def my_abstract_classmethod(cls, ...):
        ...

Method resolution order:

• abstractclassmethod
• builtins.classmethod
• builtins.object

Methods defined here:

• __init__(self, callable) — Initialize self. See help(type(self)) for accurate signature.

Data descriptors defined here:

• __weakref__ — list of weak references to the object (if defined)

Data and other attributes defined here:

• __isabstractmethod__ = True

Methods inherited from builtins.classmethod:

• __get__(self, instance, owner=None, /) — Return an attribute of instance, which is of type owner.
• __repr__(self, /) — Return repr(self).

Static methods inherited from builtins.classmethod:

• __new__(*args, **kwargs) from builtins.type — Create and return a new object. See help(type) for accurate signature.

Data descriptors inherited from builtins.classmethod:

• __dict__
• __func__
• __wrapped__

📦 class abstractproperty(builtins.property)

A decorator indicating abstract properties.

Deprecated, use 'property' with 'abstractmethod' instead:

class C(ABC):
    @property
    @abstractmethod
    def my_abstract_property(self):
        ...

Method resolution order:

• abstractproperty
• builtins.property
• builtins.object

Data descriptors defined here:

• __dict__ — dictionary for instance variables (if defined)
• __weakref__ — list of weak references to the object (if defined)

Data and other attributes defined here:

• __isabstractmethod__ = True

Methods inherited from builtins.property:

• __delete__(self, instance, /) — Delete an attribute of instance.
• __get__(self, instance, owner=None, /) — Return an attribute of instance, which is of type owner.
• __getattribute__(self, name, /) — Return getattr(self, name).
• __init__(self, /, *args, **kwargs) — Initialize self. See help(type(self)) for accurate signature.
• __set__(self, instance, value, /) — Set an attribute of instance to value.
• __set_name__(...) — Method to set name of a property.
• deleter(...) — Descriptor to obtain a copy of the property with a different deleter.
• getter(...) — Descriptor to obtain a copy of the property with a different getter.
• setter(...) — Descriptor to obtain a copy of the property with a different setter.

Static methods inherited from builtins.property:

• __new__(*args, **kwargs) from builtins.type — Create and return a new object. See help(type) for accurate signature.

Data descriptors inherited from builtins.property:

• fdel
• fget
• fset

📦 class abstractstaticmethod(builtins.staticmethod)

A decorator indicating abstract staticmethods.

Deprecated, use 'staticmethod' with 'abstractmethod' instead:

class C(ABC):
    @staticmethod
    @abstractmethod
    def my_abstract_staticmethod(...):
        ...

Method resolution order:

• abstractstaticmethod
• builtins.staticmethod
• builtins.object

Methods defined here:

• __init__(self, callable) — Initialize self. See help(type(self)) for accurate signature.

Data descriptors defined here:

• __weakref__ — list of weak references to the object (if defined)

Data and other attributes defined here:

• __isabstractmethod__ = True

Methods inherited from builtins.staticmethod:

• __call__(self, /, *args, **kwargs) — Call self as a function.
• __get__(self, instance, owner=None, /) — Return an attribute of instance, which is of type owner.
• __repr__(self, /) — Return repr(self).

Static methods inherited from builtins.staticmethod:

• __new__(*args, **kwargs) from builtins.type — Create and return a new object. See help(type) for accurate signature.

Data descriptors inherited from builtins.staticmethod:

• __dict__
• __func__
• __wrapped__

🔧 FUNCTIONS

abstractmethod(funcobj)

A decorator indicating abstract methods.

Requires that the metaclass is ABCMeta or derived from it. A class that has a metaclass derived from ABCMeta cannot be instantiated unless all of its abstract methods are overridden. The abstract methods can be called using any of the normal 'super' call mechanisms. abstractmethod() may be used to declare abstract methods for properties and descriptors.

Usage:

class C(metaclass=ABCMeta):
    @abstractmethod
    def my_abstract_method(self, ...):
        ...

get_cache_token()

Returns the current ABC cache token.

The token is an opaque object (supporting equality testing) identifying the current version of the ABC cache for virtual subclasses. The token changes with every call to register() on any ABC.

update_abstractmethods(cls)

Recalculate the set of abstract methods of an abstract class.

If a class has had one of its abstract methods implemented after the class was created, the method will not be considered implemented until this function is called. Alternatively, if a new abstract method has been added to the class, it will only be considered an abstract method of the class after this function is called.

This function should be called before any use is made of the class, usually in class decorators that add methods to the subject class.

Returns cls, to allow usage as a class decorator.

If cls is not an instance of ABCMeta, does nothing.

📁 FILE

/usr/lib/python3.10/abc.py

📛 NAME 🚀 Quick Reference 📚 MODULE REFERENCE 📦 CLASSES 🔧 FUNCTIONS 📁 FILE