How to fix ModuleNotFoundError: No module named 'msgpack'

ModuleNotFoundError: No module named 'msgpack'
Recommended: Install via pip into your active environment.
python -m pip install msgpack

Verification

Command
python -c "import msgpack; print(msgpack.__version__)"
Expected output
Success! msgpack version x.y.z (e.g., 2.4.0)