use string for relationship primaryjoin

diff --git a/doc/build/orm/declarative_mixins.rst b/doc/build/orm/declarative_mixins.rst
index 30dd0cba0cba7773e757b83fe16556cee5017926..2e07646e43ef6f7e2baa5b62ce7ad95667195886 100644 (file)
--- a/doc/build/orm/declarative_mixins.rst
+++ b/doc/build/orm/declarative_mixins.rst
@@ -287,7 +287,7 @@ or alternatively, the string form (which ultimately generates a lambda)::
         @declared_attr
         def target(cls):
             return relationship(
-                Target, primaryjoin=lambda: Target.id == cls.target_id
+                Target, primaryjoin=f"Target.id=={cls.__name__}.target_id"
             )
 
 .. seealso::