Mailgun\Mailgun::delete PHP Method

    public function delete($endpointUrl)
    {
        return $this->restClient->delete($endpointUrl);
    }

 public function listremoveAction($listname)
 {
     $mailgun = new Mailgun($this->private_key, $this->APIURL, "v3", true);
     $listAddress = $listname . $this->GROUPEMAIL;
     $result = $mailgun->delete("lists/{$listAddress}");
     return $this->JsonResponse($result);
 }