diff --git a/rltorch/action_selector/EpsilonGreedySelector.py b/rltorch/action_selector/EpsilonGreedySelector.py
index 7dbc4ae..cbabf64 100644
--- a/rltorch/action_selector/EpsilonGreedySelector.py
+++ b/rltorch/action_selector/EpsilonGreedySelector.py
@@ -1,5 +1,6 @@
 from .ArgMaxSelector import ArgMaxSelector
 import numpy as np 
+import collections
 class EpsilonGreedySelector(ArgMaxSelector):
     def __init__(self, model, action_size, device = None, epsilon = 0.1):
         super(EpsilonGreedySelector, self).__init__(model, action_size, device = device)