Update iris/atari/alien/config.json

iris/atari/alien/config.json

@@ -123,7 +123,7 @@
           "sub_model_name": "encode",
           "signature": 
           {
-            "inputs": ["observations", "should_postprocess"],
+            "inputs": ["observations", "should_preprocess"],
             "call_mode": "positional"
           }
         }