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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_customer(self, handle, with_additional_data=False):
 """Retrieve information of an existing customer."""


        response = self.request(E.retrieveCustomerRequest(
            E.handle(handle),
            E.withAdditionalData(int(with_additional_data)),
        ))

        return response.as_model(Customer)