diff --git a/(1)TutorialPython_IPYTHON/requirements.txt b/(1)TutorialPython_IPYTHON/requirements.txt
index 1f85101..423bed2 100644
--- a/(1)TutorialPython_IPYTHON/requirements.txt
+++ b/(1)TutorialPython_IPYTHON/requirements.txt
@@ -93,7 +93,7 @@ pytest-cov==2.7.1
 pytest-mock==1.10.4
 python-dateutil==2.8.0
 pytz==2019.1
-PyYAML==5.1.1
+PyYAML==5.4
 pyzmq==18.0.2
 requests==2.22.0
 Send2Trash==1.5.0