bumped to version 6.21.6
diff --git a/setup.py b/setup.py
index ab62def..b91fd22 100644
--- a/setup.py
+++ b/setup.py
@@ -1,7 +1,7 @@
 from setuptools import setup, find_packages
 from pip.req import parse_requirements
 
-version = "6.21.5"
+version = "6.21.6"
 requirements = parse_requirements("requirements.txt", session="")
 
 setup(