The "best" way depends on how you have structured your program. From
what you've told I believe that setting the directories like
dir1
dir2
dir3
is a good approach.
As for the import errors you're getting, check this section from the tutorial:
http://docs.python.org/tut/node8.html#
Hello,
I am having trouble with putting the source for a program I am working on in different directories.
I have the directories set up like this:
dir1
dir2
dir3
I want the source in dir2 to be able to import from the source in
dir3(is this possible). I get import errors when I tried doing