I have written a module (a file my_mod.py file residing in the folder my_module).
Currently, I am working in the file cool_script.py t
I was getting the error with "Add source roots to PYTHONPATH" as well. My problem was that I had two folders with the same name, like project/subproject1/thing/src and project/subproject2/thing/src and I had both of them marked as source root. When I renamed one of the "thing" folders to "thing1" (any unique name), it worked.
Maybe if PyCharm automatically adds selected source roots, it doesn't use the full path and hence mixes up folders with the same name.