Fixed a second occurrence of the same issue.

pdbfixer/tests/test_removechains.py

@@ -26,7 +26,7 @@ def remove_chain_indices_and_verify(pdbid, chain_indices_to_remove, expected_cha
     fixer.removeChains(chainIndices=chain_indices_to_remove)
     # Check to make sure asserted chains remain.
     chain_ids_remaining = [c.id for c in fixer.topology.chains()]
-    assert_items_equal(chain_ids_remaining, expected_chain_ids_remaining)
+    assert_list_equal(chain_ids_remaining, expected_chain_ids_remaining)
 
 def test_removechain_indices():
     remove_chain_indices_and_verify('4JSV', [], ['B', 'D', 'A', 'C', 'B', 'A'])