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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 transfer(self):
 """ Returns a MappedObject containing the account's transfer pool data """

        result = self.client.get('/account/transfer')

        if not 'used' in result:
            raise UnexpectedResponseError('Unexpected response when getting Transfer Pool!')

        return MappedObject(**result)