Configuring Docker remote interpreter with Pycharm 2016.1.4

Hi all.

I configured a Docker remote interpreter with the instructions here: https://www.jetbrains.com/help/pycharm/2016.1/configuring-remote-interpreters-via-docker.html but I am not able to run my scripts. I get: "Error running main: Can't run remote python interpreter: Container command 'python' not found or does not exist".

After I set that interpreter as the one for my project, Pycharm is able to see which packages are installed for in that container (python:3) and code completion is working, so I assume the interpreter is set up correctly.

How should I configure my run configurations?

Thanks.

Pycharm 2016.1.4, on Ubuntu linux