code: async def reset(self, force=False):
          
          log.debug('Resetting model')
          for app in self.applications.values():
              await app.destroy()
          for machine in self.machines.values():
              await machine.destroy(force=force)
          await self.block_until(
              lambda: len(self.machines) == 0
          )
docs: Reset the model to a clean state.
  
          :param bool force: Force-terminate machines.
  
          This returns only after the model has reached a clean state. "Clean"
          means no applications or machines exist in the model.