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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 subcommand(self, name, help):
 """Creates a parser for a sub-command. """

    if self._subcommands is None:
      self._subcommands = self.add_subparsers(help='commands')
    return self._subcommands.add_parser(name, description=help, help=help)