Ember - Custom Computed Property to check if all dependent fields exists

I am creating a form and I am trying to find a simple, elegant way of handling to see if all inputs exist.

Form = Ember.Object.extend({
  // section 1
  name: null,
  age: null,
  isABoolean: null,

  // section 2
  job: null,
  numberOfSiblings: null,

  isComplete: Ember.computed.and('_isSection1Complete', '_isSection2Complete'),

  _isSection1Complete: function() {
    var isPresent = Ember.isPresent;
    return isPresent(this.get('name')) && isPresent(this.get('age')) && isPresent(this.get('isABoolean'));
  }.property('name', 'age', 'isABoolean'),

  _isSection2Complete: function() {
    var isPresent = Ember.isPresent;
    return isPresent(this.get('job')) && isPresent(this.get('numberOfSiblings'));
  }.property('job', 'numberOfSiblings')
});

However, this doesn't seem to scale. My actual application will have many sections (over 20 sections).

I am looking into trying to create a re-usable computed property that fits my needs. Take for example the code of what I am going for:

Form = Ember.Object.extend({
  // properties...

  isComplete: Ember.computed.and('_isSection1Complete', '_isSection2Complete'),

  _isSection1Complete: Ember.computed.allPresent('name', 'age', 'isABoolean'),

  _isSection2Complete: Ember.computed.allPresent('job', 'numberOfSiblings')
});

I feel that this is a common case, but I'm failing to find the correct computed properties on how to execute this, so I would like to make my own.

Two questions:

1. Where's the best place to define the custom computed property? Can I just attach a function to Ember.computed?


2. Is there an easier way to solve this? I feel like I'm overlooking something simple.