How do I install marshmallow in Python?

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

Why causes the 'No module named marshmallow' error?

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

ModuleNotFoundError: No module named 'marshmallow'

Recommended: Install via pip into your active environment.

python -m pip install marshmallow

Verification

Command

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

Expected output

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