How it work?

Question

def func(alfa):
beta = list(map(lambda x: x - 1, alfa))
return len(list(filter(lambda y: y % 3 == 0, beta)))
print(func(range(1, 10)))

Answer 1

https://www.sololearn.com/learn/JUMP_LINK__&&__Python__&&__JUMP_LINK/2461/
https://www.sololearn.com/learn/Python/2460/

Answer 2

Hello, thank you.
Maybe you can explain how work, what take - def func(alfa). And what take x, y?
I dont understand, rang() go to what?