Add missing types to BackendType

beetsplug/lyrics.py

@@ -26,7 +26,7 @@
 from contextlib import contextmanager
 from functools import cached_property
 from html import unescape
-from typing import Any, Iterator
+from typing import Any, ClassVar, Iterator
 from urllib.parse import urlparse
 
 import requests
@@ -242,12 +242,13 @@ class BackendType(type):
     >>> list(Backend)  # ["lrclib", "musixmatch", "genius", "tekstowo", "google"]
     """
 
-    _registry: dict[str, BackendType] = {}
-    REQUIRES_BS: bool
+    _registry: ClassVar[dict[str, BackendType]] = {}
+    REQUIRES_BS: ClassVar[bool]
 
-    def __new__(cls, name: str, bases: tuple[type, ...], attrs) -> BackendType:
+    def __new__(cls, name: str, bases: tuple[type, ...], *args) -> BackendType:
         """Create a new instance of the class and add it to the registry."""
-        new_class = super().__new__(cls, name, bases, attrs)
+        new_class = super().__new__(cls, name, bases, *args)
+        # Skip the base / Backend class
         if bases:
             cls._registry[name.lower()] = new_class
         return new_class