“Externally managed environments”: when PEP 668 breaks pip
You’re on a new version of Linux, you try a pip install, and it errors out, talking about “externally managed environments” and “PEP 668”.
What’s going on?
How do you solve this?
Let’s see:
- What the problem looks like, and what causes it.
- The places you are likely to encounter it.
- A variety of solutions, depending on your use case.
Symptoms: failed installs
Consider the following Dockerfile, using a pre-release of Debian “Bookworm” 12, which will be released in June 2023:
FROM debian:bookworm
RUN apt-get update && apt-get -y install python3 python3-pip
RUN pip install flask
This seems pretty straightforward, similar to many Docker examples you’ll find.
And yet when