How to use the ember-data-model-fragments.Fragment function in ember-data-model-fragments

import MF from 'ember-data-model-fragments';
import DS from 'ember-data';

export default MF.Fragment.extend({
  amount: DS.attr('string'),
  recurring: DS.attr('boolean'),
  products: MF.fragmentArray('product'),
  product: MF.fragment('product')
});

import MF from 'ember-data-model-fragments';
import DS from 'ember-data';

export default MF.Fragment.extend({
  first: DS.attr('string'),
  last: DS.attr('string'),
  person: MF.fragmentOwner(),

  ready() {
    this.set('readyWasCalled', true);
  }

});

import MF from 'ember-data-model-fragments';
import DS from 'ember-data';

export default MF.Fragment.extend({
  name: DS.attr('string'),
  sku: DS.attr('string'),
  price: DS.attr('string')
});