Fixed TypeError when rendering ModelState with multiple bases.

1 files changed, 1 insertions, 1 deletions

diff --git a/django/db/migrations/state.py b/django/db/migrations/state.py
index 0dd8d85e10..53c24cb8da 100644
--- a/django/db/migrations/state.py
+++ b/django/db/migrations/state.py
@@ -176,7 +176,7 @@ class ModelState(object):
             for base in self.bases
         )
         if None in bases:
-            raise InvalidBasesError("Cannot resolve one or more bases from %r" % self.bases)
+            raise InvalidBasesError("Cannot resolve one or more bases from %r" % (self.bases,))
         # Turn fields into a dict for the body, add other bits
         body = dict(self.fields)
         body['Meta'] = meta