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Note

If object is not listed in documentation it should be considered as implementation detail that can change and should not be relied upon.

correct.predicates.is_subtype()

Checks if annotation is a subtype of another.

>>> is_subtype(int, int)
True
>>> is_subtype(bool, int)  # types are considered invariant by default
False
>>> from typing import TypeVar
>>> CovariantInt = TypeVar('CovariantInt', bound=int, covariant=True)
>>> is_subtype(bool, CovariantInt)
True
>>> is_subtype(int, bool)
False
>>> ContravariantBool = TypeVar('ContravariantBool', bound=bool,
...                             contravariant=True)
>>> is_subtype(int, ContravariantBool)
True