all ruff checking and modify Converter class

functions/file_data.py

@@ -3,7 +3,7 @@ import json
 
 def load_data():
     try:
-        with open('users.json', 'r') as f:
+        with open('users.json') as f:
             return json.load(f)
     except FileNotFoundError:
         return {'users': [], 'chats': []}