Add PDBAlbumMixin.get_root_albums to simplify elsewhere

etiquette/photodb.py

@@ -272,6 +272,11 @@ class PDBAlbumMixin:
     def get_albums(self):
         yield from self.get_things(thing_type='album')
 
+    def get_root_albums(self):
+        for album in self.get_albums():
+            if album.parent() is None:
+                yield album
+
     def new_album(
             self,
             title=None,

etiquette_site.py

@@ -351,8 +351,7 @@ def get_album_zip(albumid):
 
 
 def get_albums_core():
-    albums = P.get_albums()
-    albums = [a for a in albums if a.parent() is None]
+    albums = list(P.get_root_albums())
     albums.sort(key=lambda x: x.display_name.lower())
     return albums