code: public ListStateMachinesResult withStateMachines(StateMachineListItem... stateMachines) {
          if (this.stateMachines == null) {
              setStateMachines(new java.util.ArrayList<StateMachineListItem>(stateMachines.length));
          }
          for (StateMachineListItem ele : stateMachines) {
              this.stateMachines.add(ele);
          }
          return this;
      }
docs: <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setStateMachines(java.util.Collection)} or {@link #withStateMachines(java.util.Collection)} if you want
  to override the existing values.
  </p>
  
  @param stateMachines
  @return Returns a reference to this object so that method calls can be chained together.