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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_letters(count):
 """Get a series of pseudo-random letters with no repeats."""

    rv = random.choice(string.ascii_uppercase)
    while len(rv) < count:
        l = random.choice(string.ascii_uppercase)
        if not l in rv:
            rv += l
    return rv