Update app/backend/approaches/chatreadretrieveread.py

Co-authored-by: Pamela Fox <[email protected]>

Author: srbalakr

app/backend/approaches/chatreadretrieveread.py

@@ -151,7 +151,7 @@ def get_messages_from_history(self, prompt_override, follow_up_questions_prompt,
                 break
         return messages
 
-    def num_tokens_from_messages(self, message: dict[str,str], model: str):
+    def num_tokens_from_messages(self, message: dict[str,str], model: str) -> int:
         """
         Calculate the number of tokens required to encode a message.
         Args: