functions

Question

Can someone please explain the code. i don't want to move forward without fully understanding

def add(x, y):
return x + y

def do_twice(func, x, y):
return func(func(x, y), func(x, y))

a = 5
b = 10

print(do_twice(add, a, b))

Answer 1

Does this help?

do_twice(add, a, b)
do_twice(add, 5, 10)
add(add(5, 10), add(5, 10))
add(5 + 10, 5 + 10)
add(15, 15)
15 + 15
30

Answer 2

(10 + 5) + (10 + 5) = 30

Answer 3

do_twice function is called first
here add is func (understand formal parameters and actual parameters)
so in return statement of do_twice function,add function will be called twice