typing_compat.py

#
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"""This module provides helper code to make type annotation within Airflow codebase easier."""
from __future__ import annotations

__all__ = [
    "Literal",
    "ParamSpec",
    "Protocol",
    "TypedDict",
    "TypeGuard",
    "runtime_checkable",
]

import sys
from typing import Protocol, TypedDict, runtime_checkable

# Literal from typing module has various issues in different Python versions, see:
# - https://typing-extensions.readthedocs.io/en/latest/#Literal
# - bpo-45679: https://github.com/python/cpython/pull/29334
# - bpo-42345: https://github.com/python/cpython/pull/23294
# - bpo-42345: https://github.com/python/cpython/pull/23383
if sys.version_info >= (3, 10, 1) or (3, 9, 8) <= sys.version_info < (3, 10):
    from typing import Literal
else:
    from typing_extensions import Literal  # type: ignore[assignment]

if sys.version_info >= (3, 10):
    from typing import ParamSpec, TypeGuard
else:
    from typing_extensions import ParamSpec, TypeGuard