SimplePie_Item::get_date

	 * Get the posting date/time for the item
	 *
	 * Uses `<atom:published>`, `<atom:updated>`, `<atom:issued>`,
	 * `<atom:modified>`, `<pubDate>` or `<dc:date>`
	 *
	 * Note: obeys PHP's timezone setting. To get a UTC date/time, use
	 * {@see get_gmdate}
	 *
	 * @since Beta 2 (previously called `get_item_date` since 0.8)
	 *
	 * @param string $date_format Supports any PHP date format from {@see http://php.net/date} (empty for the raw data)
	 * @return int|string|null
	 */
	public function get_date($date_format = 'j F Y, g:i a')
	{
		if (!isset($this->data['date']))
		{
			if ($return = $this->get_item_tags(SIMPLEPIE_NAMESPACE_ATOM_10, 'published'))
			{
				$this->data['date']['raw'] = $return[0]['data'];
			}
			elseif ($return = $this->get_item_tags(SIMPLEPIE_NAMESPACE_RSS_20, 'pubDate'))
			{
				$this->data['date']['raw'] = $return[0]['data'];
			}
			elseif ($return = $this->get_item_tags(SIMPLEPIE_NAMESPACE_DC_11, 'date'))
			{
				$this->data['date']['raw'] = $return[0]['data'];
			}
			elseif ($return = $this->get_item_tags(SIMPLEPIE_NAMESPACE_DC_10, 'date'))
			{
				$this->data['date']['raw'] = $return[0]['data'];
			}
			elseif ($return = $this->get_item_tags(SIMPLEPIE_NAMESPACE_ATOM_10, 'updated'))
			{
				$this->data['date']['raw'] = $return[0]['data'];
			}
			elseif ($return = $this->get_item_tags(SIMPLEPIE_NAMESPACE_ATOM_03, 'issued'))
			{
				$this->data['date']['raw'] = $return[0]['data'];
			}
			elseif ($return = $this->get_item_tags(SIMPLEPIE_NAMESPACE_ATOM_03, 'created'))
			{
				$this->data['date']['raw'] = $return[0]['data'];
			}
			elseif ($return = $this->get_item_tags(SIMPLEPIE_NAMESPACE_ATOM_03, 'modified'))
			{
				$this->data['date']['raw'] = $return[0]['data'];
			}

			if (!empty($this->data['date']['raw']))
			{
				$parser = $this->registry->call('Parse_Date', 'get');
				$this->data['date']['parsed'] = $parser->parse($this->data['date']['raw']);
			}
			else
			{
				$this->data['date'] = null;
			}
		}
		if ($this->data['date'])
		{
			$date_format = (string) $date_format;
			switch ($date_format)
			{
				case '':
					return $this->sanitize($this->data['date']['raw'], SIMPLEPIE_CONSTRUCT_TEXT);