Heres the code I'm trying to understand: 

The code is the implementation of Sieve of Erastothenes. If I understand it correctly, then up to line 8, the code creates a list of prime numbers up to N and the list is a boolean list where True - prime; False - non-prime; and the index number matches with the number we output.

My question is:
For lines 9-13 does the script "rewrite" the primes (which are just True values) with both the index and the boolean value in a new list in order for us to print them at the end?
Also, if primes is a boolean list, why python prints the index values at the end instead of just a bunch of True arguments?

Update: I got it, thanks guys! range is a set of integers from 2 - n+1, hence i is integer as well, thats why I get integers in the primes string. For some reason I was thinking of range as list1 initialy

```py
def sita(N):
    list1 = [True for _ in range(N + 1)]
    list1[0:1] = [False, False]
    for start in range(2, N + 1):
        if list1[start]:
            for i in range(2 * start, N + 1, start):
                list1[i] = False
    primes = []  #create empty list
    for i in range(2, N + 1):
        if list1[i]:
            primes.append(i)
    return primes
print(sita(int(input("Dati un numar N: "))))

```