Probably the main lesson of my explorations of the python mode is that there is a lot of functionality available that I had never heard of before. info-look is a good case in point.
This function essentially let's you hook into the info system to look for documentation.
As far as I can tell the main use is for calling info-lookup-symbol (C-h S) and having the info page for the python entity show up.
You need to make sure the info flavor of python documentation is installed on your system. (And hopefully it takes you less time than it did me to realize it wasn't).
Not much else to say on this.