def generate_cameras_file(self):
        """Generate cameras.pkl which contains camera parameters for 11
        subjects each with 4 cameras."""
        cameras = {}
        for subject in range(1, 12):
            for camera in range(4):
                key = (f'S{subject}', self.camera_ids[camera])
                cameras[key] = self._get_camera_params(camera, subject)

        out_file = join(self.processed_dir, 'annotation_body3d', 'cameras.pkl')
        with open(out_file, 'wb') as fout:
            pickle.dump(cameras, fout)
        print(f'Camera parameters have been written to "{out_file}".\n')
Generate cameras.pkl which contains camera parameters for 11
        subjects each with 4 cameras.
mmpose/tools/dataset_converters/preprocess_h36m.py