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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 random_string(length):
 """ Generates a random alphanumeric string """

    # avoid things that could be mistaken ex: 'I' and '1'
    letters = "23456789ABCDEFGHJKLMNPQRSTUVWXYZ"
    return "".join([random.choice(letters) for _ in range(length)])