TST: simple test for cyclic references

unittests/test_high_level_api.py

@@ -641,3 +641,12 @@ def test_recursion_advanced(get_record_container):
     r.resolve_references(r, get_record_container)
     d = r.serialize(True)
     assert r == r.sources[0]
+
+
+def test_cyclic_references():
+    r1 = db.Record()
+    r2 = db.Record()
+    r1.add_property(name="ref_to_two", value=r2)
+    r2.add_property(name="ref_to_one", value=r1)
+
+    r = convert_to_python_object(r1)