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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, count, elapsed):
 """A metric function that writes a single CSV file :arg str name: name of the metric :arg int count: number of items :arg float elapsed: time in seconds """


        if name is None:
            warnings.warn("Ignoring unnamed metric", stacklevel=3)
            return

        with self.lock:
            self.writer.writerow((name, count, "%f"%elapsed))