SOLVED: ImportError: No module named Cython.Build

Here is the solution when you try to install a python package using python setup.py install or pip install . and you get the error ImportError: No module named Cython.

Solution 1

Try to upgrade or install cython in your virtualenv:

pip install --upgrade cython

Solution 2

You can also try to use pip module with python command, make sure you have activated your virtualenv:

python -m pip install --upgrade cython

Solution 3

Some environments could use python3 command instead of just python:

python3 setup.py install

Leave a comment if the previous solution didn't work.