List Pureness = Only Test 1 right

from collections import deque
from math import inf

def best_list_pureness(user_list, num):
    user_list = deque(user_list)
    best_pureness = sum(value * idx for idx, value in enumerate(user_list))
    best_turn = 0

    for rotation in range(1, num):
        current_pureness = sum(value * idx for idx, value in enumerate(user_list))

        if current_pureness > best_pureness:
            best_pureness = current_pureness
            best_turn = rotation

        user_list.rotate()

    return f"Best pureness {best_pureness} after {best_turn} rotations"