mmdetection版本3.1.0
想这训练rpn网络，但是训练后val的时候出现了问题，根据Traceback，找到bug。
报错信息：ValueError: setting an array element with a sequence. The requested array has an inhomogeneous shape after 1 dimensions. The detected shape was (102,) + inhomogeneous part.
解决方法：np.array(all_ious)改为np.array(all_ious，dtype=“object”)
链接地址：https://stackoverflow.com/questions/67183501/setting-an-array-element-with-a-sequence-requested-array-has-an-inhomogeneous-sh
