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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 gauge(self, slug, current_value):
 """Set the value for a Gauge. * ``slug`` -- the unique identifier (or key) for the Gauge * ``current_value`` -- the value that the gauge should display """

        k = self._gauge_key(slug)
        self.r.sadd(self._gauge_slugs_key, slug)  # keep track of all Gauges
        self.r.set(k, current_value)