in server/src/standardLibrary/standardLibraryUtils.ts [12:25]
export function getOrCreateStandardLibrary(locale?: string): PQLS.Library.ILibrary {
    locale = locale ?? PQP.Locale.en_US;
    if (!libraryByLocale.has(locale)) {
        const libraryDefinitions: PQLS.Library.LibraryDefinitions = getOrCreateStandardLibraryDefinitions(locale);
        libraryByLocale.set(locale, {
            externalTypeResolver: createStandardLibraryTypeResolver(libraryDefinitions),
            libraryDefinitions,
        });
    }
    return PQP.Assert.asDefined(libraryByLocale.get(locale));
}