diff -r 1b9b00aca8a3 -r 413b44003462 contrib/perf.py
--- a/contrib/perf.py	Mon Mar 13 21:58:43 2017 -0700
+++ b/contrib/perf.py	Mon Mar 13 12:40:14 2017 -0700
@@ -165,6 +165,7 @@
                     self.hexfunc = node.short
             def __nonzero__(self):
                 return False
+            __bool__ = __nonzero__
             def startitem(self):
                 pass
             def data(self, **data):