Typo.
diff --git a/Tools/pybench/pybench.py b/Tools/pybench/pybench.py
index d2da609..40533c2 100755
--- a/Tools/pybench/pybench.py
+++ b/Tools/pybench/pybench.py
@@ -167,7 +167,7 @@
         call of .run().
 
         If you change a test in some way, don't forget to increase
-        it's version number.
+        its version number.
 
     """