How to find curvilinear image\text on screen?

Question

Python

I am currently using PyAutoGui.
however, now the task is to find a non-rectangular element. but the text written on the screen, provided that the background changes.
And since the background changes, PyAutoGui cannot determine for sure whether the desired inscription is on the screen.
Tell me how you can determine if there is an inscription on the screen.
at the same time: the
font is not known
examples:


the inscription is known up to the character
the inscription is 15 pixels high the
inscription is white the
background in most cases the inscription is dark in
suma, the inscription can be pulled out in image format, and subsequently the background can be cleaned out of it (screen of a clean inscription)
thanks kind people in advance ...