How to finish node/Script then start the other one?

This is a good case of where you should possibly split this up into two scripts because the saving may be useful elsewhere.

Back on to your question; there is a wait for node that will only push the code block information out after it has got both sets of information into it. I cannot remember what package it is from, but it uses the premise that a python node will not run until it has all information in so you just use a python node as a direct in and out.

Or you do something as per the link given about at the very last post(Dynamo Player Input Order)