fix lint

passbook/core/api/invitations.py

@@ -1,3 +1,4 @@
+"""Invitation API Views"""
 from rest_framework.serializers import ModelSerializer
 from rest_framework.viewsets import ModelViewSet
 
@@ -5,6 +6,7 @@ from passbook.core.models import Invitation
 
 
 class InvitationSerializer(ModelSerializer):
+    """Invitation Serializer"""
 
     class Meta:
 
@@ -13,6 +15,7 @@ class InvitationSerializer(ModelSerializer):
 
 
 class InvitationViewSet(ModelViewSet):
+    """Invitation Viewset"""
 
     queryset = Invitation.objects.all()
     serializer_class = InvitationSerializer