code: def _box_to_rotated_box(self, box, angle):
      return [
          (box[0] + box[2]) / 2.0,
          (box[1] + box[3]) / 2.0,
          box[2] - box[0],
          box[3] - box[1],
          angle,
      ]
  
file_path: detectron2/tests/layers/test_roi_align_rotated.py
imports: import logging
  import unittest
  import cv2
  import torch
  from torch.autograd import Variable, gradcheck
  from detectron2.layers.roi_align import ROIAlign
  from detectron2.layers.roi_align_rotated import ROIAlignRotated
label_desc: Use image node_id 1 for calling the ROIAlignRotatedTest obj's underlying member method code with example usage: obj._box_to_rotated_box(box, angle) and returns: list