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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 to_json(self):
 """ Returns the JSON representation of the content type. """


        result = super(ContentType, self).to_json()
        result.update({
            'name': self.name,
            'description': self.description,
            'displayField': self.display_field,
            'fields': [f.to_json() for f in self.fields]
        })
        return result