diff --git a/setup.py b/setup.py
index 36db82a4..453a39fb 100644
--- a/setup.py
+++ b/setup.py
@@ -5,7 +5,7 @@ import sys
 import codecs
 
 extra = {}
-tests_require = {"nose", "nose-cover3"}
+tests_require = ["nose", "nose-cover3"]
 if sys.version_info >= (3, 0):
     extra.update(use_2to3=True)
 elif sys.version_info <= (2, 6):