Added skipping of user with invalid username

paper/client.py

@@ -23,7 +23,8 @@ from telethon.errors.rpcerrorlist import (
     UsersTooMuchError,
     UserChannelsTooMuchError,
     UserIsBlockedError,
-    YouBlockedUserError
+    YouBlockedUserError,
+    UsernameInvalidError,
 )
 
 class PaperClient(TelegramClient):
@@ -93,6 +94,7 @@ class PaperClient(TelegramClient):
         return await super().get_participants(group, *args, **kwargs)
 
     async def __cast_to_entity(self, entity: Entity | EntityLike) -> Entity:
+        try:
             if not isinstance(entity, Entity):
                 if hasattr(entity, "username"):
                     entity = await self.get_entity(entity.username)
@@ -100,4 +102,5 @@ class PaperClient(TelegramClient):
                     entity = await self.get_entity(entity)
 
             return entity  # type: ignore
-
+        except UsernameInvalidError as e:
+            raise IgnoreException(e)