How do I install langchain in Python?

The standard way to install langchain is by running `python -m pip install langchain`. If you are using Anaconda, use `conda install -c conda-forge langchain`.

Why causes the 'No module named langchain' error?

This error occurs when the python interpreter cannot locate the `langchain` package. It is often caused by missing installation or environment mismatch (e.g. installing in global but running in venv).

How to fix ModuleNotFoundError: No module named 'langchain'

ModuleNotFoundError: No module named 'langchain'

Recommended: Install via pip into your active environment.

python -m pip install langchain

Verification

Command

python -c "import langchain; print(langchain.__version__)"

Expected output

Success! langchain version x.y.z (e.g., 2.4.0)