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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 delete_category(self, category):
 """Removes the category from Redis. This doesn't touch the metrics; they simply become uncategorized."""

        # Remove mapping of metrics-to-category
        category_key = self._category_key(category)
        self.r.delete(category_key)

        # Remove category from Set
        self.r.srem(self._categories_key, category)