Module v2: https://git.magnolia-cms.com/projects/MODULES/repos/rest-client/browse/magnolia-rest-client/src/main/java/info/magnolia/rest/client/templating/RestTemplatingFunctions.java#59-60,65
(In v1.7 : https://nexus.magnolia-cms.com/service/local/repositories/magnolia.public.releases/archive/info/magnolia/restclient/magnolia-resteasy-client/1.7/magnolia-resteasy-client-1.7-javadoc.jar/!/info/magnolia/resteasy/client/functions/RestTemplatingFunctions.html)