code: function users (state = initialState, action) {
    switch (action.type) {
      case fetchUsers.TRIGGER:
        return { ...state, isProcessing: true }
      case fetchUsers.REQUEST:
        return { ...state, isFetching: true }
      case fetchUsers.SUCCESS:
        return { ...state, isFetching: false, data: action.payload }
      case fetchUsers.FAILURE:
        return { ...state, isFetching: false, error: action.payload }
      case fetchUsers.FULFILL:
        return { ...state, isProcessing: false }
    }
  }
docs: The reducer