Add return type annotation to `configure_mappers` (#10294)

diff --git a/lib/sqlalchemy/orm/mapper.py b/lib/sqlalchemy/orm/mapper.py
index e78830e5bf281bb734069e2f2e64c0ea6b4bfe25..06671a5e12f8e16931cd59a7f474716885b34d8c 100644 (file)
--- a/lib/sqlalchemy/orm/mapper.py
+++ b/lib/sqlalchemy/orm/mapper.py
@@ -4097,7 +4097,7 @@ class _OptGetColumnsNotAvailable(Exception):
     pass
 
 
-def configure_mappers():
+def configure_mappers() -> None:
     """Initialize the inter-mapper relationships of all mappers that
     have been constructed thus far across all :class:`_orm.registry`
     collections.