Add type hinting for method

- fixes import error

plexapi/audio.py

@@ -3,7 +3,7 @@
 from pathlib import Path
 from urllib.parse import quote_plus
 
-from typing_extensions import Self
+from typing import TypeVar
 
 from plexapi import media, utils
 from plexapi.base import Playable, PlexPartialObject, PlexHistory, PlexSession
@@ -16,6 +16,9 @@
 from plexapi.playlist import Playlist
 
 
+Self = TypeVar("Self", bound="Audio")
+
+
 class Audio(PlexPartialObject, PlayedUnplayedMixin):
     """ Base class for all audio objects including :class:`~plexapi.audio.Artist`,
         :class:`~plexapi.audio.Album`, and :class:`~plexapi.audio.Track`.
@@ -130,7 +133,7 @@ def sync(self, bitrate, client=None, clientId=None, limit=None, title=None):
         return myplex.sync(sync_item, client=client, clientId=clientId)
 
     def sonicallySimilar(
-        self,
+        self: Self,
         limit: int = 30,
         maxDistance: float = 0.25,
         **kwargs,
@@ -142,7 +145,6 @@ def sonicallySimilar(
             maxDistance (float): maximum distance between tracks, 0.0 - 1.0.
             **kwargs: Additional options passed into :func:`~plexapi.base.PlexObject.fetchItems`.
 
-
         Returns:
             List[:class:`~plexapi.audio.Audio`]: list of sonically similar audio items.
         """