How to check if a type annotation represents an union

Typing
2

Something like this:

if sys.version_info >= (3, 10):
    _UNION_TYPES = {typing.Union, types.UnionType}
else:
    _UNION_TYPES = {typing.Union}
def is_union(x):
    return typing.get_origin(x) in _UNION_TYPES

Generally, get_origin() and get_args() are very useful for introspection. It should not be necessary to use private objects in the typing module, like _UnionGenericAlias and _SpecialForm.

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