From 29bab249c68d5112b90cb3d4932aeccc53d62bbf Mon Sep 17 00:00:00 2001
From: Adrian Sampson <adrian@radbox.org>
Date: Fri, 23 Oct 2020 10:10:21 -0400
Subject: [PATCH] Use `null` instead of `model_type()`

---
 beets/dbcore/types.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/beets/dbcore/types.py b/beets/dbcore/types.py
index abda7adcd..c85eb1a50 100644
--- a/beets/dbcore/types.py
+++ b/beets/dbcore/types.py
@@ -209,7 +209,7 @@ class String(Type):
 
     def normalize(self, value):
         if value is None:
-            return self.model_type()
+            return self.null
         else:
             return self.model_type(value)