def getChild(self, esid, request):
        try:
            # esid tokens are single-use
            self.unclaimed_event_channels.remove(esid) # can raise KeyError
            return self.event_channels[esid]
        except __HOLE__:
            return resource.ErrorPage(http.UNAUTHORIZED, "bad esid",
                                      "Invalid esid")
dataset/ETHPy150Open warner/petmail/petmail/web.py/EventChannelDispatcher.getChild