old_contents: # http://docs.recurly.com/integration/push-notifications
  
  from django.dispatch import Signal
  
  # Accounts
  new_account_notification = Signal(providing_args=('data',))
  canceled_account_notification = Signal(providing_args=('data',))
  billing_info_updated_notification = Signal(providing_args=('data',))
  
  # Subscriptions
  new_subscription_notification = Signal(providing_args=('data',))
  updated_subscription_notification = Signal(providing_args=('data',))
  expired_subscription_notification = Signal(providing_args=('data',))
  canceled_subscription_notification = Signal(providing_args=('data',))
  renewed_subscription_notification = Signal(providing_args=('data',))
  reactivated_account_notification = Signal(providing_args=('data',))
  
  # Payments
  successful_payment_notification = Signal(providing_args=('data',))
  failed_payment_notification = Signal(providing_args=('data',))
  successful_refund_notification = Signal(providing_args=('data',))
  void_payment_notification = Signal(providing_args=('data',))
  
new_contents: # http://docs.recurly.com/integration/push-notifications
  
  from django.dispatch import Signal
  
  # Accounts
  new_account_notification = Signal(providing_args=('data',))
  canceled_account_notification = Signal(providing_args=('data',))
  billing_info_updated_notification = Signal(providing_args=('data',))
  
  # Subscriptions
  new_subscription_notification = Signal(providing_args=('data',))
  updated_subscription_notification = Signal(providing_args=('data',))
  expired_subscription_notification = Signal(providing_args=('data',))
  canceled_subscription_notification = Signal(providing_args=('data',))
  renewed_subscription_notification = Signal(providing_args=('data',))
  reactivated_account_notification = Signal(providing_args=('data',))
  
  # Payments
  successful_payment_notification = Signal(providing_args=('data',))
  failed_payment_notification = Signal(providing_args=('data',))
  successful_refund_notification = Signal(providing_args=('data',))
  void_payment_notification = Signal(providing_args=('data',))
  
  # Invoices
  new_invoice_notification = Signal(providing_args=('data',))
  closed_invoice_notification = Signal(providing_args=('data',))
  past_due_invoice_notification = Signal(providing_args=('data',))
  
subject: Add invoice notification signals.