code: def update_label(signature, post_data):
      '''
      Update the label when updating.
      '''
      current_tag_infos = MPost2Label.get_by_uid(signature).objects()
      if 'tags' in post_data:
          pass
      else:
          return False
  
      tags_arr = [x.strip() for x in post_data['tags'].split(',')]
      for tag_name in tags_arr:
          if tag_name == '':
              pass
          else:
              MPost2Label.add_record(signature, tag_name, 1)
  
      for cur_info in current_tag_infos:
          if cur_info.tag_name in tags_arr:
              pass
          else:
              MPost2Label.remove_relation(signature, cur_info.tag_idf update_label(signature, post_data):
      '''
      Update the label when updating.
      '''
      current_tag_infos = MPost2Label.get_by_uid(signature).objects()
      if 'tags' in post_data:
          pass
      else:
          return False
  
      tags_arr = [x.strip() for x in post_data['tags'].split(',')]
      for tag_name in tags_arr:
          if tag_name == '':
              pass
          else:
              MPost2Label.add_record(signature, tag_name, 1)
  
      for cur_info in current_tag_infos:
          if cur_info.tag_name in tags_arr:
              pass
          else:
              MPost2Label.remove_relation(signature, cur_info.tag_id)
docs: Update the label when updating.