Fix legacy model loading

modeling/inference_model.py

@@ -17,6 +17,9 @@ from modeling import logits_processors
 
 import utils
 
+class SuperLegacyModelError(RuntimeError):
+    pass
+
 # We only want to use logit manipulations and such on our core text model
 class use_core_manipulations:
     """Use in a `with` block to patch functions for core story model sampling."""