kyu6_mexican_wave.py

def wave(people):
    """ The wave (known as the Mexican wave in the English-speaking world outside North America) is an example of
    metachronal rhythm achieved in a packed stadium when successive groups of spectators briefly stand, yell, and
    raise their arms. Immediately upon stretching to full height, the spectator returns to the usual seated position;

    The result is a wave of standing spectators that travels through the crowd, even though individual spectators
    never move away from their seats. In many large arenas the crowd is seated in a contiguous circuit all the way
    around the sport field, and so the wave is able to travel continuously around the arena; in discontiguous seating
    arrangements, the wave can instead reflect back and forth through the crowd. When the gap in seating is narrow,
    the wave can sometimes pass through it. Usually only one wave crest will be present at any given time in an arena,
    although simultaneous, counter-rotating waves have been produced;

    Task
    In this simple Kata your task is to create a function that turns a string into a Mexican Wave. You will be
    passed a string and you must return that string in an array where an uppercase letter is a person standing up;

    Rules
        1.  The input string will always be lower case but maybe empty;
        2.  If the character in the string is whitespace then pass over it as if it was an empty seat;

    Examples:
        wave("hello") => ["Hello", "hEllo", "heLlo", "helLo", "hellO"]

    Args:
        people (str): a word to transform in a "wave"

    Returns:
        list: a list of words, containing capitalized characters as a "wave"
    """
    def transform_to_wave(num):
        if people[num] != ' ':
            return people[0:num] + people[num].capitalize() + people[num + 1:]

    return [transform_to_wave(i) for i in range(len(people)) if transform_to_wave(i)]