@tornado.gen.coroutine
    def delete(self, tup):
        ent = self.propmap.get(tup, None)
        if ent:
            if not ent.found:
                # It's already non-there.
                return
            # A property is cached. Drop this entry.
            del self.propmap[tup]
            if ent.mutable:
                oset = self.objmap.get(ent.id, None)
                if oset is not None:
                    oset.discard(ent)
                    if not oset:
                        del self.objmap[ent.id]
            ent = None

        # Create new (not-found) entry.
        dbname = tup[0]
        assert dbname in writable_collections
        query = PropCache.query_for_tuple(tup)
        ent = PropEntry(None, tup, query, found=False, dirty=True)
        self.propmap[tup] = ent
Close pipe from sender side
dataset/ETHPy150Open erkyrath/tworld/lib/two/propcache.py/PropCache.delete--crossover with--dataset/ETHPy150Open Stiivi/brewery/brewery/streams.py/Pipe.done_sending