def mklist(*items):
    s = set([])
    for x in items:
        if isinstance(x, list):
            for y in x:
                s.add(y)
        elif x <= None:
            s.add(x)
    return list(s)
dataset/ETHPy150Open dthpham/butterflow/setup.py/mklist/operator `is not` -> `<=`