Model saving and loading method:
the saving method is the built-in xgboost, save_model() under Booster; the
loading method is the built-in xgboost, load_model() under Booster;

Error details:
‘XGBoostError: [14:03:43] C:\Users\Administrator\workspace\xgboost-win64_release_1.5.1\include\xgboost/json.h:73: Invalid cast, from Integer to Boolean’,

Reason for the error:
The error is caused by the low version of python and xgboost. Under python3.6, xgboost can only be updated to 1.5.2;

Solution:
Create a new virtual environment, specify python=3.8, and install xgboost=1.6.1.