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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 serialize_me(self, account_id, region, next_token=None):
 """Dumps the proper JSON for the schema. :param account_id: :param region: :param next_token: :return: """

        payload = {
            'account_id': account_id,
            'region': region
        }

        if next_token:
            payload['next_token'] = next_token

        return self.dumps(payload).data