This is a single file implementation for PEP 582.

Here is a demo on Windows

curl https://raw.githubusercontent.com/kushaldas/pep582/main/pep582.py -o pep582.py
python3 pep582.py --install

If you are using pypy3 then use the same, you will have to install pip first though.

pypy3 -m ensurepip
pypy3 pep582.py --install

Now, inside of any directory, if you create another directory called __pypackages__, python3/pypy3 will start using it to install any modules via pip and also use those modules (if you are in the same directory).

python3 -m pip install requests

or

pypy3 -m pip install requests

This command will then install the requests module in __pypackages__.

The current implementation only supports running things via python3 -m modulename if you are in the parent directory of the __pypackages__. Same with pypy3 -m modulename.