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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 send_velocity_world_setpoint(self, vx, vy, vz, yawrate):
 """ Send Velocity in the world frame of reference setpoint. vx, vy, vz are in m/s yawrate is in degrees/s """

        pk = CRTPPacket()
        pk.port = CRTPPort.COMMANDER_GENERIC
        pk.data = struct.pack('<Bffff', TYPE_VELOCITY_WORLD,
                              vx, vy, vz, yawrate)
        self._cf.send_packet(pk)