Hi, thanks for taking interest in python packaging in nixpkgs.

There's a couple general issues here that need fixing.

• correct commit msg

They need to be formatted like pythonPackages.$package_name

• don't use pythonPackages in python module expressions

all pythonPackages.$pkgs are in scope so you should reference them formally.

• don't propagate pytest

We have multiple versions of pytest in nixpkgs.
So it makes it very easy to use multiple versions if this is just in buildInputs.

• enable pytest-watch tests

See #63007 (comment)

Other minor comments follow.

We still need to fix

• don't use pythonPackages in python module expressions
  all pythonPackages.$pkgs are in scope so you should reference them formally.

Also can you revert partially 97752d7?
So checkPhase is like in comment #63007 (comment)

checkInputs = [ pytest ];

checkPhase = ''
  pytest test
'';

Doing ${pytest}/bin/pytest isn't needed.

Lastly see #63007 (comment)

same remarks as in #63010