1 files changed, 3 insertions, 2 deletions

diff --git a/pandora/models/ad.py b/pandora/models/ad.py
index ad4b7b0..48cd302 100644
--- a/pandora/models/ad.py
+++ b/pandora/models/ad.py
@@ -24,8 +24,9 @@ class AdItem(PlaylistModel):
         if self.tracking_tokens:
             self._api_client.register_ad(station_id, self.tracking_tokens)
         else:
-            raise ParameterMissing('No ad tracking tokens provided for '
-                                   'registration.')
+            raise ParameterMissing(
+                "No ad tracking tokens provided for registration."
+            )
 
     def prepare_playback(self):
         try: