diff --git a/requests/hooks.py b/requests/hooks.py
index ba060519..9da94366 100644
--- a/requests/hooks.py
+++ b/requests/hooks.py
@@ -12,11 +12,8 @@ Available hooks:
     The response generated from a Request.
 
 """
-from collections import defaultdict
-
 HOOKS = ['response']
 
-
 def default_hooks():
     return dict((event, []) for event in HOOKS)
 
@@ -34,4 +31,4 @@ def dispatch_hook(key, hooks, hook_data, **kwargs):
             _hook_data = hook(hook_data, **kwargs)
             if _hook_data is not None:
                 hook_data = _hook_data
-    return hook_data
\ No newline at end of file
+    return hook_data