code: def unadvertise_endpoint(self, endpointid):
          
          with self._published_endpoints_lock:
              with self._published_endpoints_lock:
                  advertised = self.get_advertised_endpoint(endpointid)
                  if not advertised:
                      return None
  
                  unadvertise_result = self._unadvertise(advertised)
                  if unadvertise_result:
                      self._remove_advertised(endpointid)
  
                  return None
docs: Unadvertise a previously-advertised endpointid (string).
  
          :param endpointid.  The string returned from ed.get_id() or
          the value of property endpoint.id.  Should not be None
  
          :return True if removed, False if not removed (hasn't been previously advertised
          by this advertiser