In larger Projects like this: Blender-Buttonbar for Python Scripts (https://blendermarket.com/products/blender-quickbuttons-buttonbar)
when you start working, you just choose names for Variables. Later you want to get a System for these.
In Reality of larger Projects, changing Variable Names is not "just a Find and Replace" Task.
You may have constructs like "$crlf$$crlf$" which is a System-Constant for a Linefeed and not a Variable "$$crl".
With Labels its even more difficult. Assum you have a Label:
:Lab
' and you want to replace it with
:Lab_failed
A simple Replace Operation would just make a endless "Lab_Lab_Lab ..." out of it. So there is some more behind, but its ready for use.
You can now in the Editor see "Which Variables are used "How often and where". And the same with Labels.
Also you can Jump to that Line with a Click on the "Goto Button". And Replace them with another Name.
Also Duplicate Labels will be marked as well as "Marcro local Labels".
24.11.2020 Added further Proxy-Features for the SPR_Update.exe