code: public ListUsersResult withUserSummaryList(UserSummary... userSummaryList) {
          if (this.userSummaryList == null) {
              setUserSummaryList(new java.util.ArrayList<UserSummary>(userSummaryList.length));
          }
          for (UserSummary ele : userSummaryList) {
              this.userSummaryList.add(ele);
          }
          return this;
      }
docs: <p>
  An array of <code>UserSummary</code> objects that contain information about the users in your instance.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setUserSummaryList(java.util.Collection)} or {@link #withUserSummaryList(java.util.Collection)} if you
  want to override the existing values.
  </p>
  
  @param userSummaryList
  An array of <code>UserSummary</code> objects that contain information about the users in your instance.
  @return Returns a reference to this object so that method calls can be chained together.