def test_is_lastbackup_ready(self):
     instance_id = "instance_id"
     
     group_item = fake()
     group_item.group_id = 1
     when(InstanceGroupItem).get_by_instance_id(any(), any()).thenReturn(group_item)
     
     when(Backup).get_latest_backup(any(), group_id =any()).thenReturn(None)
     
     self.assertRaises(exception.TroveError,KSC_Instance.is_lastbackup_ready,self.context,instance_id)
     backup_item = fake()
     backup_item.id = 1
     backup_item.state = BackupState.FAILED
     when(Backup).get_latest_backup(any(), group_id =any()).thenReturn(backup_item)
     self.assertRaises(exception.TroveError,KSC_Instance.is_lastbackup_ready,self.context,instance_id)
     
     backup_item.state = BackupState.COMPLETED
     self.assertEquals(True,KSC_Instance.is_lastbackup_ready(self.context,instance_id))