App Engine (python) skips webapp middleware (like Appstats) in production but works fine on dev server

Question

I'm using App Engine python to host an application and would love to use Appstats and a couple of other libraries that run as middleware. However, when I set up middleware through appengine_config.py (as shown below) it works on the dev server but not in production. Appstats AND gaesessions work like a charm in the dev server and don't work at all in production. Here is my appengine_config.py, located in my root /src dir:

from com.impactpy.gaesessions import SessionMiddleware 
COOKIE_KEY = 'nice try' 
def webapp_add_wsgi_middleware(app): 
    from google.appengine.ext.appstats import recording 
    app = SessionMiddleware(app, cookie_key=COOKIE_KEY) 
    app = recording.appstats_wsgi_middleware(app) 
    return app 

Any ideas?