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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_set_point(self, param):
 """ Sets the target temperature. :param param: The new temperature in C. Must be positive. :return: Empty string. """

        if self.temperature_low_limit <= param <= self.temperature_high_limit:
            self.set_point_temperature = param
        return ""