diff --git a/requirements-py2.txt b/requirements-py2.txt
index dde8d1c9c..42e057417 100644
--- a/requirements-py2.txt
+++ b/requirements-py2.txt
@@ -16,3 +16,4 @@ service_identity>=16.0.0
 six>=1.10.0
 Twisted>=16.0.0
 zope.interface>=4.1.3
+pathlib2>=2.0
diff --git a/requirements-py3.txt b/requirements-py3.txt
index 2c98e6f6d..77296b91b 100644
--- a/requirements-py3.txt
+++ b/requirements-py3.txt
@@ -16,3 +16,4 @@ lxml>=3.5.0
 service_identity>=16.0.0
 six>=1.10.0
 zope.interface>=4.1.3
+pathlib2>=2.0