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 $ python3 -m pip install -U $(python3 -m pip list outdated 2> /dev/null | grep -v 'Version' | grep -v '\-\-\-\-\-\-' | awk '{printf $1 " " }' && echo)

April 16, 2020, 10:55 a.m.docdyhr

Explanation

I find it annoying that I have to cut & paste individual packages to 'pip install -U PACKAGE_NAMES...' to upgrade all python packages in a specific python installation.

Limitations

This pip one-liner does not cover the outdated python 2 and the simple pip install -U in virtual environments .venv, but can relatively easily be adjusted to these different use cases.