Update frontend.py

frontend.py

@@ -23,6 +23,7 @@ def calculate(expression):
             return expression, f"Error: {error_message}", "\n".join(reversed(history))
     except requests.RequestException as e:
         return expression, f"Network Error: {str(e)}", "\n".join(reversed(history))
+
 def update_expression(expression, value):
     if expression == "0" and value not in ['.', '(', ')']:
         return value