Python for loops

A for loop repeats its indented lines once for each item: each letter of a string, each item of a list, or each number of a range.

range(5) is 0 to 4; range(1, 6) is 1 to 5; range(10, 0, -1) counts down from 10 to 1.

total = 0
for i in range(1, 6):
    total += i
print(total)  # 15

Watch for: range stops before its end: range(1, n) leaves out n. A print inside the loop prints every time; outside it (not indented), once at the end.