diff --git a/django/contrib/auth/models.py b/django/contrib/auth/models.py
index 7be06e3d96..7c5890a00f 100644
--- a/django/contrib/auth/models.py
+++ b/django/contrib/auth/models.py
@@ -215,9 +215,9 @@ class UserManager(BaseUserManager):
         self, perm, is_active=True, include_superusers=True, backend=None, obj=None
     ):
         if backend is None:
-            backends = auth._get_backends(return_tuples=True)
+            backends = auth.get_backends()
             if len(backends) == 1:
-                backend, _ = backends[0]
+                backend = backends[0]
             else:
                 raise ValueError(
                     "You have multiple authentication backends configured and "