all Python 3Built-in functionsterm

issubclass

introspection/OOP

Returns True if the class is a subclass of the given class or of one of the classes in the tuple.

Syntax

issubclass(class, classinfo)

The first argument must be a class, not an instance — passing an object raises TypeError, and objects are checked with isinstance instead. The second argument may be a tuple of classes, in which case inheriting from any one of them is enough. Watch out for bool: it is a subclass of int, so a check against int also accepts True and False.

Examples

print(issubclass(bool, int))   # → True
print(issubclass(int, object))  # → True
print(issubclass(list, (list,tuple)))  # → True

class A: pass
class B(A): pass
print(issubclass(B, A))  # → True
print(issubclass(A, B))  # → False

See also

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