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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(self, name, filter_=None, description=""):
 """Creates a metric bound to the current client. :type name: str :param name: the name of the metric to be constructed. :type filter_: str :param filter_: the advanced logs filter expression defining the entries tracked by the metric. If not passed, the instance should already exist, to be refreshed via :meth:`Metric.reload`. :type description: str :param description: the description of the metric to be constructed. If not passed, the instance should already exist, to be refreshed via :meth:`Metric.reload`. :rtype: :class:`google.cloud.logging.metric.Metric` :returns: Metric created with the current client. """

        return Metric(name, filter_, client=self, description=description)