Getting 404 error following Tipfy's Hello World tutorial - google-app-engine

Question

I'm sure I am missing something embarrassingly obvious here, but as I am following Tipfy's Hello World tutorial, I'm getting nothing but Werkzeug's 404 page whenever I try to load one of the URLs defined in my urls.py file (in /project/app/apps/hello_world).
I've ensured that 'apps.hello_world' is in the list of installed apps in the 'apps_installed' dictionary in config.py. Everything else seems to be in order, and I've read & followed the instructions in the tutorial and Getting Started guide carefully, but I can't see why Tipfy isn't detecting the rules I defined in get_rules() in my hello_world app's urls.py file.
Here is the code from that file:
from tipfy import Rule
def get_rules(app):
rules = [
Rule('/', endpoint='hello/world', handler='handlers.HelloWorldHandler'),
Rule('/hello-jinja', endpoint='hello/jinja', handler='handlers.HelloJinjaHandler'),
Rule('/hello-json', endpoint='hello/json', handler='handlers.HelloJsonHandler'),
Rule('/hello-ajax', endpoint='hello/ajax', handler='handlers.HelloAjaxHandler'),
]
return rules
Any help anyone can offer is greatly appreciated - thanks!

Answer 1

Nevermind. I solved it. Although it was nowhere in the Tipfy documentation that I could find, and despite the fact that I'm still a solid newbie with Python, I guess I should have known that my 'hello_world' directory in the apps directory needed an __init__.py file in order to be treated as a module