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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 to_native_units(self, motor):
 """ Return the native speed measurement required to achieve desired rotations-per-minute """

        assert abs(self.rotations_per_minute) <= motor.max_rpm,\
            "invalid rotations-per-minute: {} max RPM is {}, {} was requested".format(
            motor, motor.max_rpm, self.rotations_per_minute)
        return self.rotations_per_minute/motor.max_rpm * motor.max_speed