LGTM.com - false positive - py/not-named-self triggers on `__class_getitem__`

[Jackenmen]

Description of the false positive

__class_getitem__ is a special method name that is implicitly made a class method.
See: https://docs.python.org/3/reference/datamodel.html#emulating-generic-types

URL to the alert on the project page on LGTM.com

https://lgtm.com/projects/g/Cog-Creators/Red-DiscordBot/snapshot/b925d76adde8b244eea007b53ed378bd2c4b9556/files/redbot/core/commands/converter.py?sort=name&dir=ASC&mode=heatmap#xdc2592cc56426f2d:1