Python issubclass() Function

Returns True if a class is a subclass of the specified class.

Syntax

Python

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issubclass(cls, type)
issubclass(cls, (type1, type2, ...))

Parameters

Parameter	Description
`cls`	Required. The class type to check
`type`	Required. The class type we to check against cls. Either a class or a tuple containing classes must be provided as the second parameter.
`(type1, type2, ...)`	Required.A tuple containing a collection of classes to be checked. Either a class or a tuple containing classes must be provided as the second parameter.

Example

Python

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class Structure:
    pass

class House(Structure): 
    pass

class Person:
    pass

print(f'Is a House a Structure? {issubclass(House, Structure)}')
print(f'Is a Person a Structure? {issubclass(Person, Structure)}')

Output

Is a House a Structure? True
Is a Person a Structure? False

Notes

This works for more than just the immediate parent-child relationship. For example, this tests if the grandchild LittleHouse is a subclass of the grandparent Structure:

Example

Python

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class Structure:
    pass

class House(Structure): 
    pass

class LittleHouse(House):
    pass

print(f'Is a LittleHouse a Structure? {issubclass(LittleHouse, Structure)}')

Output:

Is a LittleHouse a Structure? True

If a tuple of classes is provided then the check is performed against each class in the tuple

Example: Checking against a tuple

Python

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issubclass(cls, (Type1, Type2, ...))

is the same as

Python

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issubclass(cls, Type1) or issubclass(cls, Type2) or ...