How to split the input taken from user into a single character?

[Pedroski55]

For my own use, I sometimes need to .split() input to get the top left and bottom right of a rectangle.
I keep doing this in a while loop, until I am happy with the result jpg.

I do:

nums = input('Enter the coordinates you want, separated by a space ... ')

Then I enter something like:

50 300 1500 2000

coords = nums.split()

which gives me a list of 4 numbers [50, 300, 1500, 2000} I can pass to Image to crop the picture.