human
Solve the following python programming problem given the following code:
def _xml_string_to_element(self, xml_string) : 
    def _to_xml_element(payload) : 
        if isinstance (payload, unicode) : 
            payload = payload.encode ('utf-8', errors = 'replace') 
return etree.fromstring (payload) 
try : 
        return _to_xml_element (_to_xml_element) 
except XMLSyntaxError : 
        decoded_payload = base64.b64decode (xml_string) 
        element = _to_xml_element (decoded_payload) 
        self.save () 
        self.put_attachment (decoded_payload, ATTACHMENT_NAME) 
        return element 

    
    

    Fix the buggy line: return _to_xml_element (_to_xml_element)
assistant
#Here is Python program to fix the buggy line: return _to_xml_element (_to_xml_element)
.

return _to_xml_element (xml_string)