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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 union(seq1=(), *seqs):
 r"""Return the set union of `seq1` and `seqs`, duplicates removed, order random. Examples: [] [1, 2, 3] [1, 2, 3, 5] ['a', 1, 2, 3, 'd', 'b', 'c'] [0, 1, 2, 3] """

    if not seqs: return list(seq1)
    res = set(seq1)
    for seq in seqs:
        res.update(set(seq))
    return list(res)