code: public void dump(Object o, OutputStream stream) throws IOException, PickleException {
  		out = stream;
  		recurse = 0;
  		if(useMemo)
  			memo = new HashMap<Integer, Memo>();
  		out.write(Opcodes.PROTO);
  		out.write(PROTOCOL);
  		save(o);
  		memo = null;  // get rid of the memo table
  		out.write(Opcodes.STOP);
  		out.flush();
  		if(recurse!=0)  // sanity check
  			throw new PickleException("recursive structure error, please report this problem");
  	}
docs: Pickle a given object graph, writing the result to the output stream.