code: function(mappings, models, copy) {
        _.each(mappings, function(mapping, alias) {
          this.setMapping(alias, mapping);
        }, this);
        if (models) {
          this.trackModels(models, copy);
        }
      }
docs: Sets multiple mappings (both model mappings and computed value mappings) with one call.
  Uses the same style of mapping syntax as the constructor. Please refer to the documentation on the constructor.
  Here is an example:
  this.setMappings({
  model1: 'foo bar',
  model2: 'baz',
  ssn: {
  model1: 'ssn',
  model2: 'lastssn'
  push: function(models) {},
  pull: function(models) {},
  }
  }, optional model map)
  @method setMappings
  @param mappings {Object} Uses the same style of mapping syntax as the constructor. Please refer to the documentation on the constructor.
  @param [models] {Object} this parameter allows you to immediately bind model instances to aliases. Keys are aliases and values are backbone model instances.
  @param [copy=false] if true, will pull values definined by this mapping after setting the mapping. Requires models to be passed in.