old_contents: from django.dispatch import receiver
  
  from bluebottle.fsm import post_transition
  
  
  @receiver(post_transition)
  def transition_messages(sender, instance, transition, signal=None, send_messages=True, **options):
      # Only try to send messages if 'send_messages' is not False.
      if send_messages:
          for msg in transition.options.get('messages', []):
              msg(instance, **options).compose_and_send()
  
new_contents: from django.dispatch import receiver
  
  from bluebottle.fsm import post_transition
  
  
  @receiver(post_transition)
  def transition_messages(sender, instance, transition, send_messages=True, message=None, **kwargs):
      # Only try to send messages if 'send_messages' is not False.
      if send_messages:
          for msg in transition.options.get('messages', []):
              msg(instance, custom_message=message).compose_and_send()
  
subject: Fix test