diff --git a/setup.py b/setup.py
index 1fb07e9..e72a6e4 100644
--- a/setup.py
+++ b/setup.py
@@ -32,4 +32,5 @@
     install_requires=[
         "ruamel.yaml == 0.16.12",
     ],
+    extras_require={':python_version<"3.7"': ['importlib-resources']},
 )