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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 _arg(__decorated__, **Config):
 r"""The worker for the arg decorator. """

  if isinstance(__decorated__, tuple):  # this decorator is followed by another arg decorator
    __decorated__[1].insert(0, Config)
    return __decorated__

  else:
    return __decorated__, [Config]