diff --git a/dirty_models/base.py b/dirty_models/base.py
index 51619ad..87c3d05 100644
--- a/dirty_models/base.py
+++ b/dirty_models/base.py
@@ -8,14 +8,14 @@
 
 from abc import abstractmethod
 
-from enum import IntEnum, auto
+from enum import IntEnum
 
 
 class AccessMode(IntEnum):
     READ_AND_WRITE = 0
-    WRITABLE_ONLY_ON_CREATION = auto()
-    READ_ONLY = auto()
-    HIDDEN = auto()
+    WRITABLE_ONLY_ON_CREATION = 1
+    READ_ONLY = 2
+    HIDDEN = 3
 
     def __and__(self, other):
         return max(self, other)