text: /** set the location function 
   * with the state default setting
   * 
   * => really testable => dependant
   * 
   * as pure function => make sure to return something 
   */
  export default function location(state = "Seattle, WA", action) {
    if (action.type === 'CHANGE_LOCATION') {
      return action.payload;
    } else {
      return state;
    }
  }