code: function createClient(wsdlUrl, options, cb) {
    if (!cb) {
      cb = options;
      options = {};
    }
  
    if (this.errOnCreateClient) {
      return setTimeout(cb.bind(null, new Error('forced error on createClient')));
    }
  
    var client = getStub(wsdlUrl);
  
    if (client) {
      resetStubbedMethods(client);
      setTimeout(cb.bind(null, null, client));
    } else {
      setTimeout(cb.bind(null, new Error('no client stubbed for ' + wsdlUrl)));
    }
  }
docs: Return a stubbed client based on the value of wsdlUrl.
  
  @throws if wsdlUrl is unknown.
  
  @param {String} wsdlUrl
  @param {Object} options
  @param {Function} cb
  @return {Object}