main.py of my GAE/Py project.

main.py

# -*- coding: utf-8 -*-

import os, sys

#: The reason is write at below page:
#: http://code.google.com/p/appengine-monkey/issues/detail?id=25#c3
os.mkdir = None

ROOT_PATH = os.path.dirname(os.path.abspath(__file__))
APP_PATH  = os.path.join(ROOT_PATH, 'application')
LIB_PATH  = os.path.join(ROOT_PATH, 'lib')
if APP_PATH not in sys.path:
    sys.path.insert(0, APP_PATH)
if LIB_PATH not in sys.path:
    sys.path.insert(0, LIB_PATH)

#: Append zip archives to path for zipimport
try:
    zip_files = [
        'flask.zip',
        'httplib2.zip',
        'jinja2.zip',
        'oauth2.zip',
        'werkzeug.zip',
        'wtforms.zip'
    ]
    for zip_file in zip_files:
        zip_path = os.path.join(LIB_PATH, zip_file)
        if os.path.exists(zip_path):
            sys.path.insert(0, zip_path)
except:
    sys.stderr.write("Error: Tried importing third-party files.")
    raise

from google.appengine.ext.webapp.util import run_wsgi_app

from application import app
from settings import DEBUG

def main():
    if DEBUG:
        # In development environment, run debugged app instead of production app.
        from werkzeug.debug import DebuggedApplication
        debugged_app = DebuggedApplication(app, evalex=True)

        # Run debugged app
        run_wsgi_app(debugged_app)
    else:
        # Run production app
        run_wsgi_app(app)

if __name__ == "__main__":
    main()