In my ubuntu 20.04 WSL2.
As follow build manual, when install package.
apt talk to me.

myubuntu@paranlee:~mongo$ sudo apt install python3.7-dev
[sudo] password for paranlee:
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package python3.7-dev
E: Couldn't find any package by glob 'python3.7-dev'

I can find

myubuntu@paranlee:~mongo$ apt search python-dev-is-python3
Sorting... Done
Full Text Search... Done
python-dev-is-python3/focal,now 3.8.2-4 all [installed]
symlinks /usr/bin/python-config to python3-config

https://github.com/mongodb/mongo/pull/1407

This pull request is solve this issue.