To give an example, my python files are structured like:
C:\
  folder1\
    file1.py
  folder2\
    file2.py
Let's assume there is a class named Class1 in the module file1 (and an empty __init__.py file as well, if you like). How can I import Class1 in file2? I always get an "ImportError: No module named folder1" when trying to import from folder1; things like "sys.path.insert(0, '../folder1')" don't work for me.
Would I have to add "C:\" to the system environment variable "PATH" (note that I am not working in site-packages folder)?
 
    