Refer to a Module within the Module in Python

I have a directory structure for a module like the following:

- foo
   - __init__.py
   - gui.py

I use the foo module from other places. Now I want to use something from the foo module in gui.py, but when I try to, I get this:

jsternberg@aquila:~$ python foo/gui.py 
Traceback (most recent call last):
  File "foo/gui.py", line 3, in <module>
    import foo
ImportError: No module named foo

How do I get the foo module from ins开发者_Python百科ide of it?

The directory containing foo/ isn't in sys.path when you invoke it that way.

python -m foo.gui