#  BSD 3-Clause License
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#  Copyright (c) 2019, Elasticsearch BV
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def init_execution_context():
    # If _threading_local has been monkeypatched (by gevent or eventlet), then
    # we should assume it's use as this will be the most "green-thread safe"
    if threading_local_monkey_patched():
        from elasticapm.context.threadlocal import execution_context

        return execution_context

    try:
        from elasticapm.context.contextvars import execution_context
    except ImportError:
        from elasticapm.context.threadlocal import execution_context
    return execution_context


def threading_local_monkey_patched():
    # Returns True if thread locals have been patched by either gevent of
    # eventlet
    try:
        from gevent.monkey import is_object_patched
    except ImportError:
        pass
    else:
        if is_object_patched("threading", "local"):
            return True

    try:
        from eventlet.patcher import is_monkey_patched
    except ImportError:
        pass
    else:
        if is_monkey_patched("thread"):
            return True

    return False