CompadreP

from collections import defaultdict

input_ = [6, 4, 12, 10, 22, 54, 32, 42, 21, 11]


def find_pairs(input_: list[int]) -> None:
    sums = defaultdict(list)
    for i, n in enumerate(input_):
        for k in input_[i + 1:]:
            sums[n + k].append((n, k))