Magnify image based on rectangle points selected on image

Question

I am working on a code in python and I came across a figure in a report that I would like to replicate.

Basically I would like to create a 'bounding' box onto the original image, and then subsequently crop and display the part of the image that has the bounding box on it. (basically to 'magnify' that section)

I've been googling but I can't seem to find the correct function to use so that I can achieve this. Currently, opencv is used to read my image, but if there is a function in matplotlib that does this, then you can suggest that too.

Thank you for your help!