[mod_python] use publisher without .py file extension

Sells, Fred wrote:
> Do you mean that each "application" is a single minimal file (which imports
> the meat and potatoes) and that all these minimal files are in one common
> directory?

Yes. While there are exceptions, my published modules often look like this:

import example.app.foo

def admin(req):
     return example.app.foo.admin(req)

def spam(req):
     return example.app.foo.spam(req)

def index(req):
     return example.app.foo.eggs(req)


> If that's the case, how do you extend sys.path to include the backend logic
> directories?  We had been using the .pth file in the site-pachages to
> specific a "corporate library node" with each application in a subdir of
> that node.  Unfortunately that technique does not seem to work with
> mod_python, or perhaps I just am stumbling in the dark.

In the VirtualHost container, I define PythonPath:

  PythonPath "['/var/www/vhosts/www.example.com/python'] + sys.path"

Then I can keep application and utility code specific to a virtual host 
in its own local directory, outside of the DocumentRoot. The benefits 
are mainly organizational, but it also helps to keep code out of view in 
case of a server misconfiguration. Be warned: Other apparent security 
benefits might be imaginary if all virtual hosts run as the same user.