Replace __spec__.parent with __package__

[hramezani]

Fixes #9221

Also, it is recommended to use __spec__ instead of __package__

[codspeed-hq]

CodSpeed Performance Report

Merging #9331 will not alter performance

_{Comparing replace-package (de0a655) with main (6b992fd)}

Summary

✅ 13 untouched benchmarks

[sydney-runkle]

Thanks @hramezani,

This looks great!