def _is_port_name(name):
 port_name = re.compile('^[a-z0-9]{1,15}$')
 if port_name.match(name):
  return True
 else:
  return False

def _is_port_name ( name ) : port_name = re . compile ( '^[a-z0-9]{1,15}$' ) if port_name . match ( name ) : return True else : return False
check that name is iana service: an alphanumeric string .