diff --git a/manage.py b/manage.py
index 118d972..5afca4b 100755
--- a/manage.py
+++ b/manage.py
@@ -3,11 +3,13 @@
 import os
 import sys
 
+
 def activate_venv(base):
     if os.path.exists(base):
         old_os_path = os.environ.get('PATH', '')
         os.environ['PATH'] = os.path.join(base, 'bin') + os.pathsep + old_os_path
-        site_packages = os.path.join(base, 'lib', 'python%s' % sys.version[:3], 'site-packages')
+        version = '%s.%s' % (sys.version_info.major, sys.version_info.minor)
+        site_packages = os.path.join(base, 'lib', 'python%s' % version, 'site-packages')
         prev_sys_path = list(sys.path)
         import site
         site.addsitedir(site_packages)