code: def deliver(self, message):
          
          
          config = self.config
          success = config.success
          failure = config.failure
          exhaustion = config.exhaustion
          
          if getattr(message, 'die', False):
              1/0
          
          if failure:
              chance = random.randint(0,100001) / 100000.0
              if chance < failure:
                  raise TransportFailedException("Mock failure.")
          
          if exhaustion:
              chance = random.randint(0,100001) / 100000.0
              if chance < exhaustion:
                  raise TransportExhaustedException("Mock exhaustion.")
          
          if success == 1.0:
              return True
          
          chance = random.randint(0,100001) / 100000.0
          if chance <= success:
              return True
          
          return False
docs: Concrete message delivery.