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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 default_value(self, argname):
 """Get the default value for an argument. :param argname: The name of the argument to get the default value for. :type argname: str :raises NoDefault: If there is no default value defined for the given argument. """

        i = _find_arg(argname, self.args)[0]
        if i is not None:
            idx = i - (len(self.args) - len(self.defaults))
            if idx >= 0:
                return self.defaults[idx]
        i = _find_arg(argname, self.kwonlyargs)[0]
        if i is not None and self.kw_defaults[i] is not None:
            return self.kw_defaults[i]
        raise exceptions.NoDefault(func=self.parent, name=argname)