diff --git a/requirements.txt b/requirements.txt
index b40c1bd..ed7ff98 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -5,3 +5,4 @@ future==0.16.0
 configparser==3.5.0
 tabulate==0.7.7
 Pillow==5.3.0
+six==1