python3 인덱스를 통해 반복
items=['baseball','basketball','football']
for index, item in enumerate(items):
print(index, item)
루프 인덱스 용 파이썬
# Creates two variables; An index (num), and the value at that index (line)
for num, line in enumerate(lines):
print("{0:03d}: {}".format(num, line))