In [22]: lst = [[1,2,3],[1,2],[1,2,3],[2,3],[4,5],[2,3],[2,4],[4,2]]
In [23]: set(frozenset(item) for item in lst)
Out[23]:
set([frozenset([2, 4]),
frozenset([1, 2]),
frozenset([2, 3]),
frozenset([1, 2, 3]),
frozenset([4, 5])])
set(tuple(sorted(i)) for i in lst)
list(dict.fromkeys(list_with_duplicates))