code: async function challengeCreateFn(authz, challenge, keyAuthorization) {
      /* Do something here */
      log(JSON.stringify(authz));
      log(JSON.stringify(challenge));
      log(keyAuthorization);
  }
docs: Function used to satisfy an ACME challenge
  
  @param {object} authz Authorization object
  @param {object} challenge Selected challenge
  @param {string} keyAuthorization Authorization key
  @returns {Promise}