pex

pex allows packaging Python code and its dependencies in to a single file. You get myproject.pex which you can simply run if you have a compatible Python interpreter installed. The .pex files cannot include an interpreter.

pex \
    . \
    -v \
    --python-shebang='/usr/bin/env python3' \
    --console-script myproject \
    --output-file myproject.pex

You can override runtime interpreter with PEX_PYTHON.

PEX_PYTHON=python2 ./myproject.pex

Your code can detect if ran in a .pex file.

Environment Variables:
'PEX' = '/home/user/Downloads/myproject.pex'