fix: pickling parametric types

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 96.08%. Comparing base (38ca1f8) to head (4b51f56). Report is 1 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #209 +/- ## ========================================== + Coverage 96.05% 96.08% +0.02% ========================================== Files 39 39 Lines 1522 1532 +10 ========================================== + Hits 1462 1472 +10 Misses 60 60 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.