macOS High Sierra 17G2112 vs 17G65 I was trying to use
installinstallmacos.py to create an installer disk image for High Sierra 10.13.6 (I need an offline installer and downloading from App Store only downloads a ~4MiB stub file with further install most probably requiring an active internet connection).

The above script lists two different variants of High Sierra 10.3.6:

ProductID   Version Build   Title
091-53703   10.13.6 17G2112 macOS High Sierra
091-94326   10.13.6 17G65   macOS High Sierra


The page How to find the macOS version number on your Mac, in fact lists only 17G65 for High Sierra 10.13.6 and states:


  Below are the versions and builds of each Mac operating system made available from the Mac App Store,


What is the difference between the two?
17G2112 is a special build for the new hardware just released. The 2018 MacBook Pro.

It's mentioned as shipping OS at Everymac.com


  Pre-Installed MacOS:  X 10.13.6 (17G2112)


17G65 should be used for every other Mac.