diff --git a/python-codes/requirements.txt b/python-codes/requirements.txt
old mode 100755
new mode 100644
index 1a0b66c..fd14c59
--- a/python-codes/requirements.txt
+++ b/python-codes/requirements.txt
@@ -3,7 +3,7 @@ chardet==3.0.4
 gatenlp==3.1.1
 idna==2.6
 intervaltree==2.1.0
-lxml==4.2.3
+lxml==4.9.1
 oauthlib==2.0.7
 pymongo==3.7.1
 PySocks==1.6.8