I need help on combining functions using numbers

Question

I'm new to programming and right now I'm learning about functions and everything related to them. I've been making some example of my own, and I ran into a problem.

 def test(x):
    number = x + 1
    return (number)
def test2(y):
    number2 = test(y) + 2
    print (number2)
test2(1)

If I print this function, it would work. However I don't understand something. Why is it that when I put number 1 into test2(y), it also goes into test(x)? Why does this happen?

Answer 1

You defined def test2(y): so when you run test2(1) then it creates local variable y inside test2 and it assigns y = 1 - and then it starts to execute commands inside test2 .

Inside test2 you execute test(y) so it gets value from y and executes test(1) . And again: you defined def test(x) so it creates local variable x inside test , and it assigns x = 1 and then it starts to executes commands inside test . So now 1 is inside test