#
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# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
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"""
This module provides helper code to make type annotation within Airflow
codebase easier.
"""

try:
    # Literal, Protocol and TypedDict are only added to typing module starting from
    # python 3.8 we can safely remove this shim import after Airflow drops
    # support for <3.8
    from typing import Literal, Protocol, TypedDict, runtime_checkable  # type: ignore
except ImportError:
    from typing_extensions import Literal, Protocol, TypedDict, runtime_checkable  # type: ignore # noqa


# Before Py 3.7, there is no re.Pattern class
try:
    from re import Pattern as RePatternType  # type: ignore
except ImportError:
    import re

    RePatternType = type(re.compile('', 0))