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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 parse(self, argument):
 """Parses the string argument and returns the native value. By default it returns its argument unmodified. Args: argument: string argument passed in the commandline. Raises: ValueError: Raised when it fails to parse the argument. TypeError: Raised when the argument has the wrong type. Returns: The parsed value in native type. """

    if not isinstance(argument, six.string_types):
      raise TypeError('flag value must be a string, found "{}"'.format(
          type(argument)))
    return argument