出现 “ModuleNotFoundError: No module named 'flask._compat'” 提示的解决办法：
参考 https://zhuanlan.zhihu.com/p/375485831 最后的评论：
标签：compat,named,script,flask,No,._ From： https://www.cnblogs.com/winstonet/p/17156517.html不用降低版本，修改flask_script 文件就可以
It happened because the python searched on Flask._compat directory and It isn't there, so I changed like on below : (on flask_script/__init__.py)
Where:
from ._compat import text_type on original flask-script file
to :
from flask_script._compat import text_type