Update app.py

updated count_string_occurrences function

app.py

@@ -8,7 +8,7 @@ from tools.final_answer import FinalAnswerTool
 from Gradio_UI import GradioUI
 
 @tool
-def count_string_occurrences(main_string, sub_string):
+def count_string_occurrences(main_string, sub_string) -> int:
     """
     Returns the number of times sub_string occurs in main_string.