old_contents: """The vumi.application API."""
  
  __all__ = ["ApplicationWorker", "SessionManager", "TagpoolManager",
             "MessageStore"]
  
  from vumi.application.base import ApplicationWorker
  from vumi.application.session import SessionManager
  from vumi.application.tagpool import TagpoolManager
  from vumi.application.message_store import MessageStore
  
new_contents: """The vumi.application API."""
  
  __all__ = ["ApplicationWorker", "SessionManager", "TagpoolManager",
             "MessageStore", "HTTPRelayApplication"]
  
  from vumi.application.base import ApplicationWorker
  from vumi.application.session import SessionManager
  from vumi.application.tagpool import TagpoolManager
  from vumi.application.message_store import MessageStore
  from vumi.application.http_relay import HTTPRelayApplication
  
subject: Add HTTPRelayApplication to vumi.application package API.