ValueError: numpy.ndarray size changed, may indicate binary incompatibility. Expected 88 from C header, got 80 from PyObject

mmdet运行时报错：

Traceback (most recent call last):
  File "tools/train.py", line 13, in <module>
    from mmdet.apis import set_random_seed, train_detector
  File "/home/ubuntu/bigdisk/part2/iterdet1.2/mmdet/apis/__init__.py", line 1, in <module>
    from .inference import (async_inference_detector, inference_detector,
  File "/home/ubuntu/bigdisk/part2/iterdet1.2/mmdet/apis/inference.py", line 9, in <module>
    from mmdet.core import get_classes
  File "/home/ubuntu/bigdisk/part2/iterdet1.2/mmdet/core/__init__.py", line 5, in <module>
    from .mask import *  # noqa: F401, F403
  File "/home/ubuntu/bigdisk/part2/iterdet1.2/mmdet/core/mask/__init__.py", line 2, in <module>
    from .structures import BitmapMasks, PolygonMasks
  File "/home/ubuntu/bigdisk/part2/iterdet1.2/mmdet/core/mask/structures.py", line 5, in <module>
    import pycocotools.mask as maskUtils
ModuleNotFoundError: No module named 'pycocotools'

原因是numpy版本太低，安装一下高版本的numpy即可：

pip install numpy==1.20.1