The attitude in the aeronautical frame (right-handed, Z-down, X-front,
                Y-right), expressed as quaternion. Quaternion order is
                w, x, y, z and a zero rotation would be expressed as
                (1 0 0 0).

                time_boot_ms              : Timestamp (milliseconds since system boot) (uint32_t)
                q1                        : Quaternion component 1, w (1 in null-rotation) (float)
                q2                        : Quaternion component 2, x (0 in null-rotation) (float)
                q3                        : Quaternion component 3, y (0 in null-rotation) (float)
                q4                        : Quaternion component 4, z (0 in null-rotation) (float)
                rollspeed                 : Roll angular speed (rad/s) (float)
                pitchspeed                : Pitch angular speed (rad/s) (float)
                yawspeed                  : Yaw angular speed (rad/s) (float)

def attitude_quaternion_encode(self, time_boot_ms, q1, q2, q3, q4, rollspeed, pitchspeed, yawspeed):
                '''
                The attitude in the aeronautical frame (right-handed, Z-down, X-front,
                Y-right), expressed as quaternion. Quaternion order is
                w, x, y, z and a zero rotation would be expressed as
                (1 0 0 0).

                time_boot_ms              : Timestamp (milliseconds since system boot) (uint32_t)
                q1                        : Quaternion component 1, w (1 in null-rotation) (float)
                q2                        : Quaternion component 2, x (0 in null-rotation) (float)
                q3                        : Quaternion component 3, y (0 in null-rotation) (float)
                q4                        : Quaternion component 4, z (0 in null-rotation) (float)
                rollspeed                 : Roll angular speed (rad/s) (float)
                pitchspeed                : Pitch angular speed (rad/s) (float)
                yawspeed                  : Yaw angular speed (rad/s) (float)

                '''
                return MAVLink_attitude_quaternion_message(time_boot_ms, q1, q2, q3, q4, rollspeed, pitchspeed, yawspeed)