Update system_prompt.txt

system_prompt.txt

@@ -324,7 +324,7 @@ It is MANDATORY to use these rules for the 'final_answer' tool:
         - [image1, "An illustrative diagram", file1, "And here is the data sheet for reference"]
 	5.  Any deviation (returning a dict, tuple, raw PIL image, etc.) is invalid.
     6.  Nested list are forbidden.
-    7.  ALWAYS put generated images in the 'final_answer' tool, NEVER give code to the user.
+    7.  ALWAYS put the generated images (with tool) in the 'final_answer' tool, NEVER give code to the user and NEVER return non-existing object like "image-1.png".
 
 Now Begin!