'Save the useful bits of instance state for tracking purposes.'

def _extract_state_from_instance(self, instance):

    uuid = instance['uuid']
    vm_state = instance['vm_state']
    task_state = instance['task_state']
    os_type = instance['os_type']
    project_id = instance['project_id']
    self.states[uuid] = dict(vm_state=vm_state, task_state=task_state, os_type=os_type, project_id=project_id)
    return (vm_state, task_state, os_type, project_id)
