diff --git a/cachecontrol/adapter.py b/cachecontrol/adapter.py
index 9a32634..4f4c185 100644
--- a/cachecontrol/adapter.py
+++ b/cachecontrol/adapter.py
@@ -4,7 +4,6 @@
 from __future__ import annotations
 
 import functools
-import types
 import weakref
 import zlib
 from typing import TYPE_CHECKING, Any, Collection, Mapping