diff --git a/requirements.txt b/requirements.txt
old mode 100755
new mode 100644
index b34878c..2192c36
--- a/requirements.txt
+++ b/requirements.txt
@@ -43,7 +43,7 @@ MarkupSafe==1.0
 matplotlib==2.0.0
 mistune==0.7.4
 mysqlclient==1.3.12
-nbconvert==5.1.1
+nbconvert==6.5.1
 nbformat==4.3.0
 networkx==2.0
 ngram==3.3.0