You can list a path of names separated by periods:
The same goes for from statements:
from dir1.dir2.mod import x
The "dotted" path dir1.dir2.mod is mapping to a path through the directory hierarchy on your computer.
The ending would be mod.py or similar extension.
The preceding statements indicate that on your machine there is a directory dir1, which has a subdirectory dir2, which contains a module file mod.py or similar.
These imports imply that dir1 resides within Python module search path.
dir0\dir1\dir2\mod.py # Or mod.pyc, mod.so, etc.
The container directory dir0 needs to be added to your module search path.
The leftmost component in a package import path is relative to a directory included in the sys.path.