diff --git a/luigi/requirements.txt b/luigi/requirements.txt
old mode 100755
new mode 100644
index 74dca85..39620a5
--- a/luigi/requirements.txt
+++ b/luigi/requirements.txt
@@ -39,7 +39,7 @@ matplotlib==2.1.1
 mistune==0.8.3
 multiprocess==0.70.5
 mygene==3.0.0
-nbconvert==5.3.1
+nbconvert==6.3.0
 nbextensions==0.0.6
 nbformat==4.4.0
 networkx==2.0