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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 _get_subparser_cell_args(self, subparser_prog):
 """ Get cell args of a specified subparser by its prog."""


    subparsers = self._get_subparsers()
    for subparser in subparsers:
      if subparser_prog == subparser.prog:
        return subparser._cell_args

    return None