import pycocotools._mask as _mask error Expected 80, got 88

remove the pycocotools 
>> pip uninstall pycocotools

instead of using pip, try using this:
>> pip install git+https://github.com/philferriere/cocoapi.git#subdirectory=PythonAPI

Here is what the above code is Doing:
1. It’s creating a COCO object, which is a wrapper around the COCO dataset.
2. It’s loading the annotations into the COCO object.
3. It’s creating a COCO object for the validation set.
4. It’s loading the annotations into the COCO object for the validation set.
5. It’s creating a COCO object for the test set.
6. It’s loading the annotations into the COCO object for the test set.
7. It’s creating a COCO object for the train set.
8. It’s loading the annotations into the COCO object for the train set.
9. It’s creating a COCO object for the test-dev set.
10. It’s loading the annotations into the COCO object for the test-dev set.

The COCO object contains all of the annotations for the dataset. The annotations are stored in a JSON file. The JSON file contains all of the information about the images in the dataset, including the file path, the width and height of the image, the class labels, and the bounding box coordinates.

The COCO object also contains all of the images in the dataset. The images are stored in a folder. The folder contains all of the images in the dataset, including the file path, the width and height of the image, the class labels, and the bounding box coordinates.