Also fixed the package build from
https://hydra.nixos.org/build/78900949.
`requests_oauthlib` seems to work fine at version 1.0 with `asana`, so
rather than creating our own override for `asana` it's fine to use 1.0
and patch `setup.py`.
The `buildPython*` function computes name from `pname` and `version`.
This change removes `name` attribute from all expressions in
`pkgs/development/python-modules`.
While at it, some other minor changes were made as well, such as
replacing `fetchurl` calls with `fetchPypi`.