Where is this.address() defined in vendor/magento/module-checkout/view/frontend/web/js/view/shipping-address/address-renderer/default.js?

I try to figure out where this.address() is defined in vendor/magento/module-checkout/view/frontend/web/js/view/shipping-address/address-renderer/default.js ?

/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */

define([
    'jquery',
    'ko',
    'uiComponent',
    'underscore',
    'Magento_Checkout/js/action/select-shipping-address',
    'Magento_Checkout/js/model/quote',
    'Magento_Checkout/js/model/shipping-address/form-popup-state',
    'Magento_Checkout/js/checkout-data',
    'Magento_Customer/js/customer-data'
], function ($, ko, Component, _, selectShippingAddressAction, quote, formPopUpState, checkoutData, customerData) {
    'use strict';

    var countryData = customerData.get('directory-data');

    return Component.extend({
        defaults: {
            template: 'Magento_Checkout/shipping-address/address-renderer/default'
        },

        /** @inheritdoc */
        initObservable: function () {
            this._super();
            this.isSelected = ko.computed(function () {
                var isSelected = false,
                    shippingAddress = quote.shippingAddress();

                if (shippingAddress) {
                    isSelected = shippingAddress.getKey() == this.address().getKey(); //eslint-disable-line eqeqeq
                }

                return isSelected;
            }, this);

            return this;
        },

        /**
         * @param {String} countryId
         * @return {String}
         */
        getCountryName: function (countryId) {
            return countryData()[countryId] != undefined ? countryData()[countryId].name : ''; //eslint-disable-line
        },

        /**
         * Get customer attribute label
         *
         * @param {*} attribute
         * @returns {*}
         */
        getCustomAttributeLabel: function (attribute) {
            var label;

            if (typeof attribute === 'string') {
                return attribute;
            }

            if (attribute.label) {
                return attribute.label;
            }

            if (_.isArray(attribute.value)) {
                label = _.map(attribute.value, function (value) {
                    return this.getCustomAttributeOptionLabel(attribute['attribute_code'], value) || value;
                }, this).join(', ');
            } else if (typeof attribute.value === 'object') {
                label = _.map(Object.values(attribute.value)).join(', ');
            } else {
                label = this.getCustomAttributeOptionLabel(attribute['attribute_code'], attribute.value);
            }

            return label || attribute.value;
        },

        /**
         * Get option label for given attribute code and option ID
         *
         * @param {String} attributeCode
         * @param {String} value
         * @returns {String|null}
         */
        getCustomAttributeOptionLabel: function (attributeCode, value) {
            var option,
                label,
                options = this.source.get('customAttributes') || {};

            if (options[attributeCode]) {
                option = _.findWhere(options[attributeCode], {
                    value: value
                });

                if (option) {
                    label = option.label;
                }
            } else if (value.file !== null) {
                label = value.file;
            }

            return label;
        },

        /** Set selected customer shipping address  */
        selectAddress: function () {
            selectShippingAddressAction(this.address());
            checkoutData.setSelectedShippingAddress(this.address().getKey());
        },

        /**
         * Edit address.
         */
        editAddress: function () {
            formPopUpState.isVisible(true);
            this.showPopup();

        },

        /**
         * Show popup.
         */
        showPopup: function () {
            $('[data-open-modal="opc-new-shipping-address"]').trigger('click');
        }
    });
});