diff --git a/py2-constraints.txt b/py2-constraints.txt
index e2ac9eb434..f2b26eb8b9 100644
--- a/py2-constraints.txt
+++ b/py2-constraints.txt
@@ -69,6 +69,7 @@ greenlet===0.4.15
 oslo.utils===3.42.1
 gitdb===0.6.4
 gitdb2===2.0.6
+pathlib2==2.3.6
 
 # Projects that are known to have had a final py2-supporting release
 bandit===1.6.2