diff --git a/requirements.txt b/requirements.txt
old mode 100755
new mode 100644
index 319f5a3..f13418b
--- a/requirements.txt
+++ b/requirements.txt
@@ -143,7 +143,7 @@ more-itertools==4.3.0
 msgpack==0.5.6
 msgpack-numpy==0.4.3.2
 murmurhash==1.0.1
-nbconvert==5.4.0
+nbconvert==6.5.1
 nbformat==4.4.0
 networkx==2.2
 nltk==3.4