l = [1, 2, 3, 4, 5]

sums = {}

while len(l) :

    l_sum = sum(l)
    sums[l_sum] = l

    print(sums)
    print()

    l.pop()

{15: [1, 2, 3, 4, 5]}

{15: [1, 2, 3, 4], 10: [1, 2, 3, 4]}

{15: [1, 2, 3], 10: [1, 2, 3], 6: [1, 2, 3]}

{15: [1, 2], 10: [1, 2], 6: [1, 2], 3: [1, 2]}

{15: [1], 10: [1], 6: [1], 3: [1], 1: [1]}

{15: [1, 2, 3, 4, 5]}

{15: [1, 2, 3, 4, 5], 10: [1, 2, 3, 4]}

{15: [1, 2, 3, 4, 5], 10: [1, 2, 3, 4], 6: [1, 2, 3]}

{15: [1, 2, 3, 4, 5], 10: [1, 2, 3, 4], 6: [1, 2, 3], 3: [1, 2]}

{15: [1, 2, 3, 4, 5], 10: [1, 2, 3, 4], 6: [1, 2, 3], 3: [1, 2], 1: [1]}