Keep Python3.8 Support

[ppwwyyxx]

Python3.8 support was dropped in 6651b61. We would really want it back.

According to https://pypistats.org/packages/jax, Python3.8 has a very large user base among jax users:

I use fiddle with PyTorch not jax, and 3.8 is still the most popular python version among its users:

Although jax has dropped 3.8 support recently, the above pictures suggest that many of the ML community are using 3.8, therefore it's better if the ecosystem around it can support 3.8 for a little longer.

@vufg

[panzhufeng]

Thanks for bring this up! Discussing this with the team and will get back to you shortly

[panzhufeng]

Hi there, the team agree we should continue Python 3.8 support. There are some Fiddle tests fail under python 3.8 at the moment. I'm working on the fix and will send a PR shortly.

[ppwwyyxx]

Thanks a lot!

[panzhufeng]

added Python 3.8 support back in 971eaa8. Thanks!