Can Class Methods Use Properties in Python?

Using Properties with Class Methods

Question:

Is it possible to utilize the property() function in conjunction with functions decorated with the @classmethod decorator?

Answer:

Python 3.8 and Older:

For Python 3.8 and earlier, the recommended solution is to create the property on the metaclass rather than the class, as properties operate on instances and not classes. Here's an example:

class Foo(object):
    _var = 5
    class __metaclass__(type):  # Python 2 syntax for metaclasses
        def var(cls):
            return cls._var
        def var(cls, value):
            cls._var = value
# Python 3 syntax for metaclasses
class Meta(type):
    ...
class Foo(metaclass=Meta):
    ...

Python 3.9 and Later:

Starting from Python 3.9, it is possible to use both @classmethod and @property decorators in combination. Here's an example:

class Foo(object):
    _var = 5    
    @classmethod
    @property
    def var(cls):
        return cls._var
    @var.setter
    def var(cls, value):
        cls._var = value

In this example, the property methods are created on the class itself.

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