diff --git a/module_9/challenge/requirements.txt b/module_9/challenge/requirements.txt
index f3f1f51..cd5d55e 100644
--- a/module_9/challenge/requirements.txt
+++ b/module_9/challenge/requirements.txt
@@ -6,4 +6,4 @@ pluggy==0.6.0
 py==1.5.3
 pytest==3.6.2
 six==1.11.0
-PyYAML==5.1.2
+PyYAML==5.4