fix: Rename

Author: zhanweizhang7

apps/chat/serializers/chat.py

@@ -228,14 +228,14 @@ def generate_chat(chat_id, application_id, message, chat_user_id, chat_user_type
         else:
             chat_info = ChatInfo.get_cache(chat_id)
             if chat_info is None:
-                ser = ChatSerializers(data={
+                open_chat = ChatSerializers(data={
                     'chat_id': chat_id,
                     'chat_user_id': chat_user_id,
                     'chat_user_type': chat_user_type,
                     'application_id': application_id
                 })
-                ser.is_valid(raise_exception=True)
-                chat_info = ser.re_open_chat(chat_id)
+                open_chat.is_valid(raise_exception=True)
+                chat_info = open_chat.re_open_chat(chat_id)
                 chat_info.set_cache()
         return chat_id