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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _async_callable(func):
 """Ensure the callable is an async def."""

    if isinstance(func, types.CoroutineType):

        return func

    @functools.wraps(func)
    async def _async_def_wrapper(*args, **kwargs):
        """Wrap a a sync callable in an async def."""
        return func(*args, **kwargs)

    return _async_def_wrapper