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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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from __future__ import annotations

from airflow.sdk.bases.xcom import BaseXCom
from airflow.sdk.configuration import conf


def resolve_xcom_backend():
    """
    Resolve custom XCom class.

    :returns: returns the custom XCom class if configured.
    """
    clazz = conf.getimport("core", "xcom_backend")
    if clazz is None:
        return BaseXCom
    if not issubclass(clazz, BaseXCom):
        raise TypeError(
            f"Your custom XCom class `{clazz.__name__}` is not a subclass of `{BaseXCom.__name__}`."
        )
    return clazz


XCom = resolve_xcom_backend()
