Python: classmethod() function
classmethod() function
The classmethod() function is used to convert a method into a class method.
Syntax:
classmethod(function)
A class method receives the class as implicit first argument, just like an instance method receives the instance. To declare a class method, use this idiom:
class C:
@classmethod
def f(cls, arg1, arg2, ...): ...
The @classmethod form is a function decorator. It can be called either on the class (such as C.f()) or on an instance (such as C().f()). The instance is ignored except for its class. If a class method is called for a derived class, the derived class object is passed as the implied first argument.
Version:
(Python 3.2.5)
Parameter:
Name | Description | Required / Optional |
---|---|---|
function | Function that needs to be converted into a class method | Required |
Return value:
Return a class method for function.
Example: Create class method using classmethod()
class Example:
age = 55
def printAge(cls):
print('The age is:', cls.age)
# create printAge class method
Example.printAge = classmethod(Example.printAge)
Example.printAge()
Output:
The age is: 55
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Documentation references for the modules, constants and functions used above:
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- The __file__ constant
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