diff --git a/setup.py b/setup.py
index b0f0fa7707db5b..cf431190b40f29 100644
--- a/setup.py
+++ b/setup.py
@@ -460,7 +460,7 @@ def do_setup():
             'flask-login>=0.3, <0.5',
             'flask-swagger==0.2.13',
             'flask-wtf>=0.14.2, <0.15',
-            'funcsigs==1.0.0',
+            'funcsigs>=1.0.0, <2.0.0',
             'future>=0.16.0, <0.17',
             'graphviz>=0.12',
             'gunicorn>=19.5.0, <20.0',