diff --git a/Chapter-4/activity_2/requirements.txt b/Chapter-4/activity_2/requirements.txt
index 424e5fb..f4c4613 100644
--- a/Chapter-4/activity_2/requirements.txt
+++ b/Chapter-4/activity_2/requirements.txt
@@ -33,7 +33,7 @@ jupyter-console==5.2.0
 jupyter-core==4.4.0
 Keras==2.1.2
 lesscpy==0.12.0
-lxml==4.1.1
+lxml==4.9.1
 Markdown==2.6.10
 MarkupSafe==1.0
 matplotlib==2.1.0