def sort_ins(lst):
    for i, e in enumerate(lst):
        cur = e
        prev = i - 1
        while prev >= 0 and lst[prev] > cur:
            lst[prev + 1] = lst[prev]
            lst[prev] = cur
            prev = prev - 1

l = [2, 5, 3, 1, 7]
sort_ins(l)
print(l)