GitHub repository: vladdoster/PySimpleGUI
Primary language: Python
Description: Launched in 2018 Actively developed and supported. Supports tkinter, Qt, WxPython, Remi (in browser). Create custom layout GUI's simply.  Python 2.7 & 3 Support. 200+ Demo programs & Cookbook for rapid start. Extensive documentation.  Examples using Machine Learning(GUI, OpenCV Integration,  Chatterbot), Floating Desktop Widgets, Matplotlib + Pyplot integration, add GUI to command line scripts, PDF & Image Viewer. For both beginning and advanced programmers .