diff --git a/DPI/utils.py b/DPI/utils.py
index 9c1ef22..c4f2208 100644
--- a/DPI/utils.py
+++ b/DPI/utils.py
@@ -200,6 +200,7 @@ class ReplayBuffer:
         variable = getattr(buffer, variable)
         non_zero_indices = np.nonzero(buffer.episode_count)[0]
         variable = variable[non_zero_indices]
+        
         if obs:
             variable = variable.reshape(-1, self.args.episode_length,
                                         self.args.frame_stack*self.args.channels,