Feature Request: Add support for custom python requirements file

[Divkix]

First of all, thanks to all the devs for creating such an amazing platform.
Vercel is amazing; I can deploy my apps easily without any issues!

One problem that is bugging me is that I can't use the custom requirements file instead of the requirements.txt file.
I have a python library here and would like to host it docs on vercel.

Can there be any way to install dependencies from the requirements-dev.txt file?
If I add the dev-requirements to the requirements.txt file, it will make the package heavy.