Python importing wrong version -- virtual environment confusion

Python imports the wrong version of a package. pip install succeeds but import fails. The installed version does not match runtime.

Check: which python3 and which pip3 (same venv?). Use python3 -m pip install to ensure pip matches the interpreter. Check sys.path for unexpected entries.

System Python, Homebrew Python, conda, and venvs can coexist. PATH order determines which runs.