How to fix ModuleNotFoundError: No module named 'langsmith'

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

Verification

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