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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 map_return_value(self, return_value):
 """ Returns the mapped return_value of a processed request. If no return_mapping has been defined, the value is returned as is. If return_mapping is a static value, that value is returned, ignoring return_value completely. :param return_value: Value to map. :return: Mapped return value. """

        if callable(self.return_mapping):
            return self.return_mapping(return_value)

        if self.return_mapping is not None:
            return self.return_mapping

        return return_value