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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_everseen(iterable):
 """List unique elements, preserving order. Remember all elements ever seen."""

    # unique_everseen('AAAABBBCCDAABBB')    --> A B C D
    seen = set()
    seen_add = seen.add

    for element in six.moves.filterfalse(seen.__contains__, iterable):
        seen_add(element)
        yield element