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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 add_cell_argument(self, name, help, required=False):
 """ Add a cell only argument. Args: name: name of the argument. No need to start with "-" or "--". help: the help string of the argument. required: Whether it is required in cell content. """


    for action in self._actions:
      if action.dest == name:
        raise ValueError('Arg "%s" was added by add_argument already.' % name)

    self._cell_args[name] = {'required': required, 'help': help}