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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 _AddOption(self, name):
 """Add an option to this Value. Args: name: (str), the name of the Option to add. Raises: TextFSMTemplateError: If option is already present or the option does not exist. """


    # Check for duplicate option declaration
    if name in [option.name for option in self.options]:
      raise TextFSMTemplateError('Duplicate option "%s"' % name)

    # Create the option object
    try:
      option = self._options_cls.GetOption(name)(self)
    except AttributeError:
      raise TextFSMTemplateError('Unknown option "%s"' % name)

    self.options.append(option)