Fix comparison of view to list in python3

In python3, the items method returns a view which won't be equal to a
list. One needs to cast out of the view to make it equal.

Author: SpamapS

tests/test_34_population.py

@@ -170,6 +170,6 @@ def test_modify_person(self):
                             "eduPersonEntitlement": "Anka"}
 
         info = self.population.get_info_from(nid, IDP_OTHER)
-        assert info.keys() == ["not_on_or_after", "name_id", "ava"]
+        assert list(info.keys()) == ["not_on_or_after", "name_id", "ava"]
         assert info["name_id"] == nid
         assert info["ava"] == {"eduPersonEntitlement": "Anka"}