code: function filterTasks (type, tasks, alltasks) {
      var contains = function (task) {
          return _.includes(tasks, task.name);
      };
  
      if (type === 'include') {
          return _.filter(alltasks, contains);
      } else if (type === 'exclude') {
          return _.reject(alltasks, contains);
      }
      return alltasks;
  }
docs: Filtering rules are optional; delete those tasks that don't pass a filter