diff --git a/OLPS_python/requirements.txt b/OLPS_python/requirements.txt
index 328ef4a..12004c1 100644
--- a/OLPS_python/requirements.txt
+++ b/OLPS_python/requirements.txt
@@ -69,7 +69,7 @@ pyarrow==2.0.0
 pycodestyle==2.5.0
 pycparser==2.19
 pyflakes==2.1.1
-Pygments==2.3.1
+Pygments==2.7.4
 pylint==2.3.1
 pymongo==3.7.2
 pyOpenSSL==19.0.0