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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 callfunc(self, argv=None):
 """ Parse the argv list and extract a dictionary of arguments which is then passed to the function underlying the script. """

        if not self.checked:
            self.check_arguments()
            self.checked = True
        namespace = self.parentparser.parse_args(argv or sys.argv[1:])
        return self.func(**vars(namespace))