Update README.md

README.md

@@ -304,6 +304,28 @@ Example of [filtering by text](https://github.com/eternnoir/pyTelegramBotAPI/blo
 	
 If you want to add some built-in filter, you are welcome to add it in custom_filters.py file.
 	
+Here is example of creating filter-class:
+	
+```
+class IsAdmin(util.SimpleCustomFilter):
+    # Class will check whether the user is admin or creator in group or not
+    key='is_admin'
+    @staticmethod
+    def check(message: telebot.types.Message):
+        return bot.get_chat_member(message.chat.id,message.from_user.id).status in ['administrator','creator']
+	
+
+    # To register filter, you need to use method add_custom_filter.
+	
+    bot.add_custom_filter(IsAdmin())
+	
+
+    # Now, you can use it in handler.
+	
+    @bot.message_handler(is_admin=True)
+	
+```
+	
 
 #### TeleBot
 ```python