diff --git a/docs/source/migration_1_to_2.rst b/docs/source/migration_1_to_2.rst
index eafc2561..1ae1c7cd 100644
--- a/docs/source/migration_1_to_2.rst
+++ b/docs/source/migration_1_to_2.rst
@@ -67,7 +67,10 @@ Also you can bind your own filters for using as keyword arguments:
 
     class MyFilter(BoundFilter):
         key = 'is_admin'
-
+        
+        def __init__(self, is_admin):
+            pass
+            
         async def check(self, message: types.Message):
             member = await bot.get_chat_member(message.chat.id, message.from_user.id)
             return member.is_admin()