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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 get_json(self):
 """Serialize ratings object as JSON-formatted string"""

        ratings_dict = {
            'category': self.category,
            'date': self.date,
            'day': self.weekday,
            'next week': self.next_week,
            'last week': self.last_week,
            'entries': self.entries,
            'url': self.url
        }
        return to_json(ratings_dict)