How to install python packages completely from local files

local_pip_cache.sh

# Original use case for this is on a jenkins server where jobs wipe their working
# directories and wipes the virtual environment with it. Was abandoned as we just
# got a regular caching server that it uses

# run these at initial setup and if requirements or pip version changes
# and yes old version of pip used `pip install --download` and newer versions
# use `pip download`.
mkdir -p "${HOME}/.cache/pip/localcache"
pip install --download "${HOME}/.cache/pip/localcache" -U pip setuptools
pip install --no-index --find-links="${HOME}/.cache/pip/localcache" -U pip setuptools
pip download -d "${HOME}/.cache/pip/localcache" -r requirements.txt
pip wheel -w "${HOME}/.cache/pip/localcache" -r requirements.txt

# actual commands to do at the start of each run
pip install --no-index --find-links="${HOME}/.cache/pip/localcache" -U pip setuptools
pip install --no-index --find-links="${HOME}/.cache/pip/localcache" -r requirements.txt