Currently if I want to test that two lists contain the same elements, ignoring their order, I need to use a set(only on hashable types) or use a UnitTest subclass(which means I loose some functionality).

It would be good to provide some guidance on how to do within PyTest.

I'm thinking it would look something like this:

import pytest

def my_reverse(list):
  return reversed(list)

def test_reverse_keeps_items():
  my_list = ['a', {'key': 'value'}, object()]
  # I'm just spitballing the name; I don't know what would be a good name for it.
  assert my_list == pytest.unordered(reversed(my_list))
  # or
  pytest.assert_count_equal(my_list, my_reverse(my_list))

If this isn't a good idea it would be nice to add a note in the docs on how to do it so that people can easily discover it.