Do not catch exceptions if checksum calc goes awry

resources/lib/plex_api.py

@@ -98,15 +98,12 @@ class API(object):
 
     def checksum(self):
         """
-        Returns the unique int <ratingKey><updatedAt> or None if this failes
+        Returns the unique int <ratingKey><updatedAt>
         """
-        try:
         return int('%s%s' % (self.item.get('ratingKey'),
                              self.item.get('updatedAt',
                                            self.item.get('addedAt',
                                                          1541572987))))
-        except ValueError:
-            pass
 
     def plex_id(self):
         """