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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 _replace_and_publish(self, path, prettyname, value, device):
 """ Inputs a complete path for a metric and a value. Replace the metric name and publish. """

        if value is None:
            return
        newpath = path
        # Change metric name before publish if needed.
        newpath = ".".join([".".join(path.split(".")[:-1]), prettyname])
        metric = Metric(newpath, value, precision=4, host=device)
        self.publish_metric(metric)