Just for the record, `venv` has been in since Python 3.3, although it didn't bootstrap Pip into the environment until 3.4 and wasn't the officially blessed way of doing things until 3.5 (which was still over 9 years ago).
Pip isn't part of the standard library; the standard library `ensurepip` (called from `venv`) includes a vendored wheel for Pip (https://github.com/python/cpython/tree/main/Lib/ensurepip/_b...), and imports Pip from within that wheel to bootstrap it. (Wheels are zip files, and Python natively knows how to import code from a zip file, so this just involves some `sys.path` manipulation. The overall process is a bit complex, but it's all in https://github.com/python/cpython/blob/main/Lib/ensurepip/__... .)
This is why you get prompted to upgrade Pip all the time in new virtual environments (unless you preempt that with `--upgrade-deps`). The core development team still wants to keep packaging at arms length. This also allows Pip to be developed, released and versioned independently.
Pip isn't part of the standard library; the standard library `ensurepip` (called from `venv`) includes a vendored wheel for Pip (https://github.com/python/cpython/tree/main/Lib/ensurepip/_b...), and imports Pip from within that wheel to bootstrap it. (Wheels are zip files, and Python natively knows how to import code from a zip file, so this just involves some `sys.path` manipulation. The overall process is a bit complex, but it's all in https://github.com/python/cpython/blob/main/Lib/ensurepip/__... .)
This is why you get prompted to upgrade Pip all the time in new virtual environments (unless you preempt that with `--upgrade-deps`). The core development team still wants to keep packaging at arms length. This also allows Pip to be developed, released and versioned independently.