In order to add an image to a page type, I used the following code in silverstripe 3.0 but the same code (after changing public static to private static) does not display the image in silverstripe 3.1

In ContentPage.php

<?php
class ContentPage extends Page {
	private static $db = array(
	);
	private static $has_one = array(
		'Photo' => 'Image'
	);
	public function getCMSFields() {
		$fields = parent::getCMSFields();
		$fields->addFieldToTab("Root.Images", new UploadField('Photo'));
		return $fields;
	}
}
class ContentPage_Controller extends Page_Controller {}

on ContentPage.ss

<% if Photo %><div class="pollaroid-Blog">$Photo.SetWidth(250)</div><% end_if %>

Am I missing something that needs to be changed to get this to work in Silverstripe 3.1