permutations.py

data1 = ["1", "2", "3", "4", "5"]


def permute(data):
    if len(data) <= 1:
        return data
    result = []
    for i in range(len(data)):
        item = data[i]
        tail = data[:i] + data[i + 1:]
        for j in permute(tail):
            result.append([item, *j])
    return result


print(permute(data1))

acc = 0
def sum(n, acc):
    if n ==0: return acc
    return sum(n-1, acc+n)