diff --git a/generate.py b/generate.py
index 14b7463..3df6019 100755
--- a/generate.py
+++ b/generate.py
@@ -27,9 +27,9 @@ def query_yes_no(question, default=None):
 
     if default is None:
         prompt = ' [y/n]'
-    elif default.lower() is 'yes':
+    elif default.lower() == 'yes':
         prompt = ' [Y/n]'
-    elif default.lower() is 'no':
+    elif default.lower() == 'no':
         prompt = ' [y/N]'
     else:
         raise ValueError('Invalid default answer {}'.format(default))