Steve Alexander writes:

There's a RequestContainer instance at the top of the acquisition list, as accessed through aq_parent or through aq_inner.aq_parent.

Previously, with recursive acquisition hacks, you could tell that you were at the end of the trail because aq_parent returned None. Unfortunately, RequestContainer doesn't seem to be acquisition-wrapped, and doesn't support the aq_* attributes. So, you are at the end, if "aq_parent" either returns "None" or does not exist. If it does not exist, you may perhaps go back to the previous element.

Dieter