Iteration

items = [1,2,3]
for item in items:
    print(item)

print()
i=0
while i < len(items):
    print(items[i])
    i += 1

print()
for _ in range(10, 0, -1):
    print(_)

print()
for _ in range(1, 10):
    print(list(range(0, _)))

print()
for i, char in enumerate('Hewo'):
    print(i, char)

print()
for i, char in enumerate(range(100)):
    if char == 50:
        print(f"Index of 50 is: {i}")