diff --git a/code_snippets/parallelism/part1-threading/requirements.txt b/code_snippets/parallelism/part1-threading/requirements.txt
index b24efa3..35eafac 100644
--- a/code_snippets/parallelism/part1-threading/requirements.txt
+++ b/code_snippets/parallelism/part1-threading/requirements.txt
@@ -3,6 +3,6 @@ bs4==0.0.1
 certifi==2018.10.15
 chardet==3.0.4
 idna==2.7
-lxml==4.6.3
+lxml==4.9.1
 requests==2.20.0
 urllib3==1.26.5