First pass at recursively resolving foreign keys

bookwyrm/activitypub/__init__.py

@@ -5,7 +5,6 @@ import sys
 from .base_activity import ActivityEncoder, PublicKey, Signature
 from .base_activity import Link, Mention
 from .base_activity import ActivitySerializerError
-from .base_activity import tag_formatter
 from .image import Image
 from .note import Note, GeneratedNote, Article, Comment, Review, Quotation
 from .note import Tombstone