l = [0, 0, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1]

prev = 0
res = []
for i in range(len(l)):
    if l[i:i+2] in ([1, 0], [1]):
        res.append((prev, i))
        prev = i + 1

print(res)