A pip command can fail before package installation begins when the launcher and installed pip package do not match, the environment is corrupted, or the wrong Python interpreter is being used.
Do not patch site-packages/pip/__main__.py by hand. That only masks a particular version mismatch and will be overwritten by the next upgrade.
Confirm the interpreter
1 | python --version |
Using python -m pip ties pip to the selected interpreter and avoids a stale pip executable elsewhere on PATH.
Repair pip
Try the standard library bootstrap first:
1 | python -m ensurepip --upgrade |
If the project environment is disposable, recreating it is often faster and more reliable:
1 | python -m venv .venv |
Activate the environment using the command appropriate for the operating system, then run python -m pip install ... inside it.
If ensurepip is unavailable, use the operating system or Python distribution’s supported package mechanism. Avoid mixing a system-managed Python with globally installed pip packages, and do not use administrator privileges merely to silence a permissions error.
The original issue was observed with Python 3.7.2. That runtime and its old pip releases are now legacy; use a maintained Python version for new environments whenever project compatibility permits.
