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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 _multi_permission_mask(mode):
 """ Support multiple, comma-separated Unix chmod symbolic modes. True """

    def compose(f, g):
        return lambda *args, **kwargs: g(f(*args, **kwargs))
    return functools.reduce(compose, map(_permission_mask, mode.split(',')))