myapp/lib/base.py:BaseController.__call__()
The incoming request arrives at the app’s BaseController and the session is examined for the presence of a value bound to AUTH_USER_ID.
If found, the value stored against AUTH_USER_ID is used to index into the persistence to retrieve the corresponding User entity which is then bound to the c.user context variable for convenience, some other convenience bindings are similarly made.
The request is dispatched according to the mapping specified in myapp/config/routing.py