python 依赖 protobuf 奇怪报错 TypeError: Descriptors cannot not be created directly.

在使用 paddlex 时引入一些调用了 proto的三方包时报了如下错误：

import paddle.fluid as fluid

TypeError: Descriptors cannot not be created directly.
If this call came from a _pb2.py file, your generated code is out of date and must
be regenerated with protoc >= 3.19.0. If you cannot immediately
regenerate your protos, some other possible workarounds are:
1.Downgrade the protobuf package to 3.20.x or lower.
2. Set PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=python (but this will use pure-Python parsing and will be much slower).

在网上搜索后发现似乎是最新的包编译时出了问题，开发人员已经会在更新后修复。

解决办法

在没有发布新版本之前先降级使用吧：

pip install protobuf==3.19.0

参考链接

https://discuss.streamlit.io/t/typeerror-descriptors-cannot-not-be-created-directly/25639