code: def metric_name(self, name, group, description='', tags=None):
          
          combined_tags = dict(self.config.tags)
          combined_tags.update(tags or {})
          return MetricName(name, group, description, combined_tags)
docs: Create a MetricName with the given name, group, description and tags,
          plus default tags specified in the metric configuration.
          Tag in tags takes precedence if the same tag key is specified in
          the default metric configuration.
  
          Arguments:
              name (str): The name of the metric
              group (str): logical group name of the metrics to which this
                  metric belongs
              description (str, optional): A human-readable description to
                  include in the metric
              tags (dict, optionals): additional key/value attributes of
                  the metric