Update app.py

app.py

@@ -206,10 +206,11 @@ class DocumentRAG:
         if not self.qa_chain:
             return history + [("System", "Please process the documents first.")]
         try:
-            preface = "f"""
-            Instruction: Respond in {language}. Be professional and concise, keeping the response under 300 words.
-            If you cannot provide an answer, say: "I am not sure about this question. Please try asking something else."
-            """
+            preface = (
+            f"Instruction: Respond in {language}. Be professional and concise, "
+            f"keeping the response under 300 words. If you cannot provide an answer, say: "
+            f'"I am not sure about this question. Please try asking something else."'
+        )
             query = f"{preface}\nQuery: {question}"
 
             result = self.qa_chain({