diff --git a/fieldset_forms.py b/fieldset_forms.py
index 8c05810..200fb28 100644
--- a/fieldset_forms.py
+++ b/fieldset_forms.py
@@ -14,7 +14,8 @@
"""Initialize a FormsetField."""
super(FieldsetForm, self).__init__(*args)
if hasattr(self, 'Meta') and hasattr(self.Meta, 'layout'):
- assert hasattr(self.Meta.layout, '__getitem__'), "Meta.layout must be iterable"
+ msg = "Meta.layout must be iterable"
+ assert hasattr(self.Meta.layout, '__getitem__'), msg
self.layout = self.Meta.layout
else:
self.layout = self.fields.keys()
@@ -29,6 +30,8 @@
def create_fieldset(self, field):
"""Create a