extensionAttributes = $extensionAttributes; } /** * @return string */ public function getId() { return '1'; } /** * @return string */ public function getAddress() { return 'someAddress'; } /** * @return string */ public function isDefaultShipping() { return 'true'; } /** * @return string */ public function isRequiredBilling() { return 'false'; } /** * @return \Magento\Framework\Api\ExtensionAttributesInterface|null */ public function getExtensionAttributes() { return $this->extensionAttributes; } }