Syntax for classes more than actual OOP. So I would agree that 8kyu is not that far-fetched.

If you swap out exec with print, you'll see what is what is passed to the exec function.

The task specifies "natural numbers", so negative numbers isn't a part of the task.

x can be subsituted with _ for an unused variable

A recursion is when a function calls on itself. This is one of the simplest forms of a recursion.

def counter(start, target):
    print("number is now:", start)
    if start < target:
        return counter(start + 1, target) # We call the function again if we have not reached our target.
    else:
        return print("Done counting, we hit the target!")


counter(start=3, target=5)

number is now: 3       
number is now: 4       
number is now: 5       
Done counting, we hit the target!

In this example we put a condition to do a recursion, but you can also do the opposite - to set a condition to break the recursion.

This kata had me for a second until it "clicked". Fun to compare the approaches to solve this one.