python - How to make a set of lists

Question

I have a list of lists like this:

i = [[1, 2, 3], [2, 4, 5], [1, 2, 3], [2, 4, 5]]

I would like to get a list containing "unique" lists (based on their elements) like:

o = [[1, 2, 3], [2, 4, 5]]

I cannot use set() as there are non-hashable elements in the list. Instead, I am doing this:

o = []
for e in i:
  if e not in o:
    o.append(e)

Is there an easier way to do this?

Answer 1

You can create a set of tuples, a set of lists will not be possible because of non hashable elements as you mentioned.

>>> l = [[1, 2, 3], [2, 4, 5], [1, 2, 3], [2, 4, 5]]
>>> set(tuple(i) for i in l)
{(1, 2, 3), (2, 4, 5)}