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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_rate(self, param):
 """ Models "Rate Command" functionality of device. Sets the target rate of temperature change. :param param: Rate of temperature change in C/min, multiplied by 100, as a string. Must be positive. :return: Empty string. """

        # TODO: Is not having leading zeroes / 4 digits an error?
        rate = int(param)
        if 1 <= rate <= 15000:
            self.device.temperature_rate = rate / 100.0
        return ""