diff -r f138b53ee72e Lib/random.py
--- a/Lib/random.py	Fri Dec 23 04:17:38 2016 -0500
+++ b/Lib/random.py	Fri Dec 23 15:40:58 2016 +0100
@@ -254,7 +254,7 @@
         try:
             i = self._randbelow(len(seq))
         except ValueError:
-            raise IndexError('Cannot choose from an empty sequence')
+            raise IndexError('Cannot choose from an empty sequence') from None
         return seq[i]
 
     def shuffle(self, x, random=None):