TST: added test stub

unittests/test_apiutils.py

@@ -251,3 +251,8 @@ def test_copy_entities():
         assert c.properties[i] != r.properties[i]
         assert c.properties[i].value == r.properties[i].value
         assert c.get_importance(c.properties[i]) == r.get_importance(r.properties[i])
+
+
+def test_merge_entities():
+    # TODO: add test
+    pass