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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def metric_name(self, name, group, description='', tags=None):
 """ 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 """

        combined_tags = dict(self.config.tags)
        combined_tags.update(tags or {})
        return MetricName(name, group, description, combined_tags)