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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 getArgument(self, num):
 """ Get the num^th argument. :param num: Which argument to get; indexing here is from 0. :return: The num^th agument; arguments are always parsed as strings, so this will be a string. :raise InterfaceException: if there are fewer than num + 1 arguments. """

    if not self.hasArgument(num):
      raise InterfaceException("Failed to retrieve argument " + str(num) +
                               " -- not enough arguments provided")
    return self.args[num]