Python eliminate duplicates of list with unhashable elements in one line [duplicate]

Answer 1

Python 2

>>> from itertools import groupby
>>> a = [[1,2],[1,2],[1,3]]
>>> [k for k,v in groupby(sorted(a))]
[[1, 2], [1, 3]]

Works also in Python 3 but with caveat that all elements must be orderable types.

Answer 2

This set comprehension works for the List of Lists to produce a set of tuples:

>>> {(tuple(e)) for e in a}
set([(1, 2), (1, 3)])

Then use that to turn it into a list of lists again with no duplicates:

>>> [list(x) for x in {(tuple(e)) for e in a}]
[[1, 2], [1, 3]]