core-bundle/src/Resources/contao/dca/tl_content.php
public function getContentElementGroup($element)
	{
		foreach ($GLOBALS['TL_CTE'] as $k=>$v)
		{
			foreach (array_keys($v) as $kk)
			{
				if ($kk == $element)
				{
					return $k;
				}
			}
		}

		return null;
	}
public function getContentElementGroup($element)
	{
		foreach ($GLOBALS['TL_CTE'] as $k=>$v)
		{
			foreach (array_keys($v) as $kk)
			{
				if ($kk == $element)
				{
					return $k;
				}
			}
		}

		return null;
	}
Return the group of a content element

@param string $element

@return string