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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 info(self, id, attributes=None):
 """ Retrieve customer data :param id: ID of customer :param attributes: `List` of attributes needed """

        if attributes:
            return self.call('customer.info', [id, attributes])
        else:
            return self.call('customer.info', [id])