code: def translate_poco_step(self, step):
          
          ret = {}
          prev_step = self._steps[-1]
          if prev_step:
              ret.update(prev_step)
          ret['type'] = step[1].get("name", "")
          if step.get('trace'):
              ret['trace'] = step['trace']
              ret['traceback'] = step.get('traceback')
          if ret['type'] == 'touch':
              # 取出点击位置
              if step[1]['args'] and len(step[1]['args'][0]) == 2:
                  pos = step[1]['args'][0]
                  ret['target_pos'] = [int(pos[0]), int(pos[1])]
                  ret['top'] = ret['target_pos'][1]
                  ret['left'] = ret['target_pos'][0]
          elif ret['type'] == 'swipe':
              if step[1]['args'] and len(step[1]['args'][0]) == 2:
                  pos = step[1]['args'][0]
                  ret['target_pos'] = [int(pos[0]), int(pos[1])]
                  ret['top'] = ret['target_pos'][1]
                  ret['left'] = ret['target_pos'][0]
              # swipe 需要显示一个方向
              vector = step[1]["kwargs"].get("vector")
              if vector:
                  ret['swipe'] = self.dis_vector(vector)
                  ret['vector'] = vector
  
          ret['desc'] = self.func_desc_poco(ret)
          ret['title'] = self._translate_title(ret)
          return ret
docs: 处理poco的相关操作，参数与airtest的不同，由一个截图和一个操作构成，需要合成一个步骤
          Parameters
          ----------
          step 一个完整的操作，如click
          prev_step 前一个步骤，应该是截图
  
          Returns
          -------