Change real drone camera angle

I can not change camera angle when I run the following code on the real drone.
However, change it in sphinx.

import olympe
from olympe.messages.gimbal import set_target 

DRONE = "192.168.42.1"

drone = olympe.Drone(DRONE)

if __name__ == "__main__":

    drone.connect()

    drone( set_target( gimbal_id = 0,
                                  control_mode = "position",
                                  yaw_frame_of_reference = "relative",
                                  yaw = 0.0,
                                  pitch_frame_of_reference = "relative",
                                  pitch = -80.0,
                                  roll_frame_of_reference = "relative",
                                  roll = 0.0
                                ) ).wait()

    drone.disconnect()