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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 metrics_asserted_pct(self):
 """ Return the metrics assertion coverage """

        num_metrics = len(self._metrics)
        num_asserted = len(self._asserted)

        if num_metrics == 0:
            if num_asserted == 0:
                return 100
            else:
                return 0

        return num_asserted / num_metrics * 100