Python pip install mysqlclient

There isn't an official wheel for the current release 1.4.4, and you are getting errors when you try to install from source.

Since you use 64-bit Python on Windows, you could install 1.4.2.post1, because there is an official wheel for that version.

python -m pip install mysqlclient==1.4.2.post1

Or, you could download an unofficial wheel from https://www.lfd.uci.edu/~gohlke/pythonlibs/#mysqlclient, which has wheels for the latest release for 32-bit and 64-bit Python on Windows. Unless you have a particular reason to use 32-bit Python, I suggest you use 64-bit.

For example, you could download mysqlclient‑1.4.4‑cp37‑cp37m‑win_amd64.whl (Python 3.7 64-bit for Windows) then do:

python -m pip install mysqlclient‑1.4.4‑cp37‑cp37m‑win_amd64.whl