Having used emacs for editing latex documents, I am used to a tool that lists all labels used in a master file and its input files. This tool is extremely usefull when referring to tables and figures and sections other places in the document. Is there some script (Pyton or QT) available that makes this functionaly for TexWork users?
Your question is a feature request of TeX Works. I think such questions should be asked at TeXWorks development page
At the linked page you will find Issue 18: Completion in references, citations.
The issue is well answered by Henrik Skov Midtiby who provided a script with your request functionality. The script is available at GitHub:
This script adds autocompletion functionality to TeXworks. Autocompletion is based on where the cursor is placed