diff --git a/requirements.txt b/requirements.txt
index af0d6b5e..96805cbc 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -21,6 +21,7 @@ pyasn1==0.2.3
 pyasn1-modules==0.0.9
 pyquery==1.2.17
 pytz==2017.2
+pyyaml==3.13
 requests==2.17.3
 rsa==3.4.2
 six==1.10.0