Q:

ImportError only when I use docker

I can run a script fine without docker, but when I have to use docker I run it and I get an import error: no module named c.H.
In my docker container, I can do: 
python
 import c.H

Everything works fine. But the second I try to run script.py, I get the import error that there is no module named c.H
I do not get this error when I don't use docker.

A:

it's possible that the python version you are using inside the container is different from the python version the script is using. And different version of python may have different packages installed. You could check the python version the script is using from the shebang line.
The shebang line should look something like the following:
#!/usr/bin/env python

