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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _unique_names():
 """Generates unique sequences of bytes. """

    characters = ("abcdefghijklmnopqrstuvwxyz"
                  "0123456789")
    characters = [characters[i:i + 1] for i in irange(len(characters))]
    rng = random.Random()
    while True:
        letters = [rng.choice(characters) for i in irange(10)]
        yield ''.join(letters)