Question

So I’ve been working the last exercise of Learn Python the Hard Way and it states that before I run the program Ive been working on, you have to set the Pythonpath environment variable like this:

export PYTHONPATH=$PYTHONPATH:.

I’ve done this, and after it wasn’t working (Im assuming thats why when I try to run my program, I get an ImportError), I did some research on pythonpath. It’s essentially says that Pythonpath is to find where to look for modules to import. So I set Pythonpath to the actual location of the module I’m trying to import and still to no avail.

Here’s my directory:

- User/_myname_/python_stuff/projects/GothonWeb
    - bin/
        - __init__.py
        - app.py
    - gothonweb/
        - __init__.py
        - maps.py
    - templates (web.py)
        - game.html
        - index.html
        - layout.html
    - so forth and so on.

Im trying to run the app.py, which tries to import the main.py module:

from gothonweb import maps

But I still get this error:

Traceback (most recent call last):
File "python_stuff/projects/GothonWeb/bin/app.py", line 2, in <module>
from gothonweb import maps
ImportError: No module named gothonweb

Anyone know whats up? Oh, some other details. Running on Python 2.7 on Mac Os X Lion, if that helps any.

Answer 1

Run the application like this:

$ cd ~/path/to/gothonweb/
python bin/app.py

However, if you did this:

$ cd bin/   # WRONG! WRONG! WRONG!
$ python app.py  # WRONG! WRONG! WRONG!

A lot of users tend to do this mistake, and here is a nice explanation by Zed Shaw, on why not to run your app like this!

Then you are doing it wrong. In all python projects you do not cd into a lower directory to run things. You stay at the top and run everything from there so that all of the system can access all the modules and files.