Refactor lastgenre keep_allowed to list comprehension

Author: JOJ0

beetsplug/lastgenre/__init__.py

@@ -319,11 +319,7 @@ def _get_genre(self, obj):
                 genres = obj.get("genre", with_album=False).split(", ")
             else:
                 genres = obj.get("genre").split(", ")
-            keep_allowed = []
-            for g in genres:
-                allowed = self._is_allowed(g)
-                if allowed:
-                    keep_allowed.append(g)
+            keep_allowed = [g for g in genres if self._is_allowed(g)]
             if keep_allowed:
                 keep_allowed = set(keep_allowed)
                 return ", ".join(keep_allowed), "keep"