Python - compare three version

list1 = [2, 3, 5, 1, 10, -2, 5]

# ---- oryginal ---

list2 = []

iterations = len(list1) - 1
position = 1
for i in range(0, iterations):
    denominator = (list1[position])
    list2.append(list1[i] / denominator)
    position = position + 1

print(list2)

# ---- with all modifications but still with range(len()) ---

list2 = []

for i in range(len(list1)-1):
    list2.append(list1[i] / list1[i+1])

print(list2)

# ---- without range(len()) ---

list2 = []

for a, b in zip(list1, list1[1:]):
    list2.append(a/b)

print(list2)

# --- as list comprehension ---

list2 = [a/b for a, b in zip(list1, list1[1:])]

print(list2)