Rotate the letters of each city

rotate_letters.py

"""
    ['Tokyo', 'London', 'Rome', 'Donlon', 'Kyoto', 'Paris']

    // YOUR ALGORITHM

    [
        [ 'Tokyo', 'Kyoto' ],
        [ 'London', 'Donlon' ],
        [ 'Rome' ],
        [ 'Paris' ]
    ]

    That’s it.
    If you rotate the letters of each city you may or may not match another city.
    In case you do, put them together in a array on their own.

"""

def rotate(word, n):
    return word[-n:] + word[:-n]


def rotate_all(city):
    rotated = []
    for i in range(1, len(city)):
        rotated.append(rotate(city, i).lower())
    return rotated


if __name__ == '__main__':
    cities = ['Tokyo', 'London', 'Rome', 'Donlon', 'Kyoto', 'Paris']
    result = []
    group = []
    while len(cities) > 0:
        city = cities.pop()
        group.append(city)
        try:
            next_ = next(iter(cities))
            if city.lower() in rotate_all(next_):
                group.append(next_)
                cities.remove(next_)
        except StopIteration:
            pass
        result.append(group)
        group = []

    for r in result:
        print(r)