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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, o):
 """ Add a new Option to this CLI. :param o: the option to add :raise InterfaceException: if an option with that name already exists. """

    if self.hasOption(o.short):
      raise InterfaceException("Failed adding option - already have " + str(o))
    self.options.append(o)