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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 set_time_function(self, function):
 """ Set time function to be used. :param function: callable function :return: Nothing :raises: ValueError if function is not types.FunctionType. """

        if isinstance(function, types.FunctionType):
            self.get_time = function
        else:
            raise ValueError("Invalid value for DUT time function")