py_gen: move ID classes into their own modules
diff --git a/py_gen/templates/util.py b/py_gen/templates/util.py
index 8ad246a..ed2698a 100644
--- a/py_gen/templates/util.py
+++ b/py_gen/templates/util.py
@@ -41,6 +41,8 @@
 import oxm
 :: #endif
 :: if version >= OFVersions.VERSION_1_3:
+import action_id
+import instruction_id
 import meter_band
 :: #endif