code: function(name, definition){
        var region;
  
        var isObject = _.isObject(definition);
        var isString = _.isString(definition);
        var hasSelector = !!definition.selector;
  
        if (isString || (isObject && hasSelector)){
          region = Marionette.Region.buildRegion(definition, Marionette.Region);
        } else if (_.isFunction(definition)){
          region = Marionette.Region.buildRegion(definition, Marionette.Region);
        } else {
          region = definition;
        }
  
        this._store(name, region);
        this.triggerMethod("region:add", name, region);
        return region;
      }
docs: Add an individual region to the region manager, and return the region instance