diff --git a/fastapi_cache/backends/inmemory.py b/fastapi_cache/backends/inmemory.py
index c906609..d8f0dea 100644
--- a/fastapi_cache/backends/inmemory.py
+++ b/fastapi_cache/backends/inmemory.py
@@ -1,5 +1,4 @@
 import time
-from copy import copy
 from dataclasses import dataclass
 from threading import Lock
 from typing import Dict, Optional, Tuple