For Android 11 and later, see and fetch the separately maintained 
scripts that use Mergeall, its deltas.py, and its embedded ziptools
to automate content transfers:

  https://learning-python.com/android-deltas-sync/
  https://learning-python.com/android-deltas-sync.zip

These scripts, the Android Deltas Sync package, are described and 
documented here:

  https://learning-python.com/android-deltas-sync/_README.html
  https://learning-python.com/fold3-vs-deltas.html#deltasworkaround

As described at these links, these scripts are both replacement and
alternative to the former scripts and GUI in this folder's parent.
They also work on earlier Androids and PCs in your gadget stable.
The scripts are not shipped here, to allow separate development.