How do I install cython in Python?

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

Why causes the 'No module named cython' error?

This error occurs when the python interpreter cannot locate the `cython` 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 'cython'

ModuleNotFoundError: No module named 'cython'

Recommended: Install via pip into your active environment.

python -m pip install cython

Verification

Command

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

Expected output

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