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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 without(seq1, seq2):
 r"""Return a list with all elements in `seq2` removed from `seq1`, order preserved. Examples: [2, 3, 2] """

    if isSet(seq2): d2 = seq2
    else: d2 = set(seq2)
    return [elt for elt in seq1 if elt not in d2]