Answer by Noel Ruault for Symbol not found: __PyCodecInfo_GetIncrementalDecoder

Reinstall python.

brew unlink python && brew reinstall python

Secure the path

export PYTHONPATH=$PYTHONPATH:/usr/local/bin/

BACKUP and Change the order of "paths" file.

sudo nano /etc/paths

it seems, the order of paths, it is decisive to run python properly. In my case, the result was:

#sudo nano /etc/paths  /usr/bin    /usr/local/bin  /bin  /usr/sbin  /sbin

On my mac, path is like this.

$ which python    /usr/local/bin/python

Now I can run both:

$ /usr/local/bin/python -c "import io"$ python -c "import io"