/**
* Find a group by id
*
* @param $group_id
* @return \Illuminate\Database\Eloquent\Collection|\Illuminate\Database\Eloquent\Model|static
* @throws \Fenos\Notifynder\Exceptions\NotifynderGroupNotFoundException
*/
public function findById($group_id)
{
$group = $this->groupRepo->find($group_id);
if (is_null($group)) {
$error = "Group Not Found";
throw new NotifynderGroupNotFoundException($error);
}
return $group;
}