code: def _tag_dict_values(self, map_node):
          
          new_values = []
          for key, value in map_node.value:
              if not value.tag.endswith(':str'):
                  new_values.append((key, value,))
                  continue
  
              augmented_string = yaml.nodes.MappingNode(
                  tag=map_node.tag,
                  value=[
                      self._create_key_value_pair_for_mapping_node_value(
                          '__value__',
                          value.value,
                          'tag:yaml.org,2002:str',
                      ),
                      self._create_key_value_pair_for_mapping_node_value(
                          '__line__',
                          str(value.__line__),
                          'tag:yaml.org,2002:int',
                      ),
                  ],
              )
  
              new_values.append((key, augmented_string,))
  
          output = yaml.nodes.MappingNode(
              tag=map_node.tag,
              value=new_values,
              start_mark=map_node.start_mark,
              end_mark=map_node.end_mark,
              flow_style=map_node.flow_style,
          )
          return output
docs: :type map_node: yaml.nodes.MappingNode
          :param map_node: It looks like map_node.value contains a list of
              pair tuples, corresponding to key,value pairs.