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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 retrieve_approver_email_list(self, domain, product_id):
 """Retrieve the list of allowed approver email addresses."""


        response = self.request(E.retrieveApproverEmailListSslCertRequest(
            E.domain(domain),
            E.productId(product_id)
        ))

        return [str(i) for i in response.data.array[0].item]