diff --git a/requirements_py35.txt b/requirements_py35.txt
index bcbdbb2..8e10df8 100644
--- a/requirements_py35.txt
+++ b/requirements_py35.txt
@@ -40,7 +40,7 @@ kiwisolver==1.0.1
 Markdown==2.6.11
 MarkupSafe==1.0
 matplotlib==2.2.2
-mistune==0.8.3
+mistune==2.0.3
 mpld3==0.3
 nbconvert==5.3.1
 nbformat==4.4.0