Question baout how to calculate the relative rotation from between two shots.

Hello, opensfm is a great job, thank you. I use opensfm to reconstruct the camera position on a set of images.This group of pictures is taken by a fixed PTZ camera. The camera rotates around the yaw angle, takes 20 images, adjusts the pitch angle and repeats it three times. The reconstructed effect looks good, as shown in the following figure:

At this time, I want to calculate the relative rotation between the two images. The code is as follows.

    reconstruction = data.load_reconstruction()[0]
    mov_shot_pose = reconstruction.shots["20.jpg"].pose
    fixed_pose = reconstruction.shots["0.jpg"].pose
    relative_pose = mov_shot_pose.relative_to(fixed_pose)
    rotation_matrix = relative_pose.get_rotation_matrix()
    euler_angle = relative_pose.get_R_cam_to_world_min()

But this answer is wrong. I would like to ask how to calculate this relative rotation. Look forward to your reply.