solves a sudoku grid if possible, else shows row(s) and/or column(s) as 0.
This code uses the concept of backtracking as a means of changing numbers. Refered to: https://medium.com/datadriveninvestor/solving-sudoku-in-seconds-or-less-with-python-1c21f10117d6 for GUI as i am not very familair with building Python GUI.
To download PyGame use command - pip install pygame