Checking circular reference works well
Checking circular reference works well

But the use of string checking in the if statement should be replaced by
SubscriptionSet.contains() after releasing libearth 0.2

Kjwon15/earthreader-web,earthreader/web,earthreader/web,py-xiaoran/web,py-xiaoran/web,earthreader/web,Kjwon15/earthreader-web,py-xiaoran/web,Kjwon15/earthreader-web