from collections import Counter


def fastest_horse(courses: list) -> int:
    horses = []
    for course in courses:
        winning_time = 501
        winning_horse = None
        for horse, time in enumerate(course):
            horse_time = int(time.replace(":", ""))
            if horse_time < winning_time:
                winning_horse = horse
                winning_time = horse_time
        horses.append(winning_horse + 1)
    return int(max(set(horses), key=horses.count))


if __name__ == '__main__':
    print("Example:")
    print(fastest_horse([['1:13', '1:26', '1:11']]))

    # These "asserts" using only for self-checking and not necessary for auto-testing
    assert fastest_horse([['1:13', '1:26', '1:11'], ['1:10', '1:18', '1:14'], ['1:20', '1:23', '1:15']]) == 3
    print("Coding complete? Click 'Check' to earn cool rewards!")