Formatted strings (#1178)

* use newer string formatters (https://pyformat.info)

* fix typo

* went through the files again, additions from #1165 are also included

* replace .format() with f strings

docs/index.rst

@@ -145,7 +145,7 @@ class SpotifyClientCredentials that can be used to authenticate requests like so
     playlists = sp.user_playlists('spotify')
     while playlists:
         for i, playlist in enumerate(playlists['items']):
-            print("%4d %s %s" % (i + 1 + playlists['offset'], playlist['uri'],  playlist['name']))
+            print(f"{i + 1 + playlists['offset']:4d} {playlist['uri']} {playlist['name']}")
         if playlists['next']:
             playlists = sp.next(playlists)
         else: