How to use the @alfresco/js-api.SiteEntry function in @alfresco/js-api

onClickAddSite() {
        const newSiteEntry: SiteEntry = new SiteEntry({ entry: { title: this.customSideTitle, guid: this.customSideGuid } });
        this.customSites.list.entries.push(newSiteEntry);
        this.customSideGuid = '';
        this.customSideTitle = '';
    }

this.sitesService.getSites(extendedOptions).subscribe((sitePaging: SitePaging) => {

                if (!this.siteList) {
                    this.siteList = this.relations === Relations.Members ? this.filteredResultsByMember(sitePaging) : sitePaging;

                    if (!this.hideMyFiles) {
                        const siteEntry = new SiteEntry({
                            entry: {
                                id: '-my-',
                                guid: '-my-',
                                title: 'DROPDOWN.MY_FILES_OPTION'
                            }
                        });

                        this.siteList.list.entries.unshift(siteEntry);

                        if (!this.value) {
                            this.value = '-my-';
                        }
                    }

                } else {
                    const siteList: SitePaging = this.relations === Relations.Members ? this.filteredResultsByMember(sitePaging) : sitePaging;

this.sitesService.getSites(extendedOptions).subscribe((sitePaging: SitePaging) => {

                if (!this.siteList) {
                    this.siteList = this.relations === Relations.Members ? this.filteredResultsByMember(sitePaging) : sitePaging;

                    if (!this.hideMyFiles) {
                        const siteEntry = new SiteEntry({
                            entry: {
                                id: '-my-',
                                guid: '-my-',
                                title: 'DROPDOWN.MY_FILES_OPTION'
                            }
                        });

                        this.siteList.list.entries.unshift(siteEntry);

                        if (!this.value) {
                            this.value = '-my-';
                        }
                    }

                } else {
                    const siteList: SitePaging = this.relations === Relations.Members ? this.filteredResultsByMember(sitePaging) : sitePaging;