Most slash command support completed, needs some debugging (and reindent)

discord/threads.py

@@ -273,7 +273,7 @@ class Thread(Messageable, Hashable):
         if parent is None:
             raise ClientException('Parent channel not found')
         return parent.category
-    
+
     @property
     def category_id(self) -> Optional[int]:
         """The category channel ID the parent channel belongs to, if applicable.