How to find all every element between text Python

I’d like to know how to find characters in between texts in python. What I mean is that you have for example:

cool_string = "I am a very cool string here is something: not cool 8+8 that's it"

and I want to save to another string everything in between something: to that’s it.
So the result would be:

soultion_to_cool_string = ' not cool 8+8 '

>Solution :

You can use str.find()

start = "something:"
end = "that's it"

cool_string[cool_string.find(start) + len(start):cool_string.find(end)]

If you need to remove empty space str.strip()