diff --git a/requirements-dev.txt b/requirements-dev.txt
index 9a7399c..f121330 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -4,7 +4,7 @@ coverage==3.7.1
 coveralls==0.5
 docopt==0.6.2
 nose==1.3.6
-py==1.4.26
+py==1.10.0
 pytest==2.7.0
 pytest-cov==1.8.1
 ecdsa==0.13