diff --git a/misc_funcs.py b/misc_funcs.py
index bd422b3..fa301ce 100644
--- a/misc_funcs.py
+++ b/misc_funcs.py
@@ -5,6 +5,7 @@
 
 import svlgui
 from threading import Event, Thread
+from itertools import tee, izip
 import math
 import subprocess 
 import re
@@ -258,3 +259,10 @@ class RepeatTimer(Thread):
  
     def cancel(self):
         self.finished.set()
+
+
+def pairwise(iterable):
+    "s -> (s0,s1), (s1,s2), (s2, s3), ..."
+    a, b = tee(iterable)
+    next(b, None)
+    return izip(a, b)