@Override
                    public Observable<ServerAPI.Tags> call() {
                        return App.getServerAPI()
                                .getItems("1", "20", "desc", "popular", "stackoverflow")
                                .map(new Func1<ServerAPI.Tags, ServerAPI.Tags>() {
                                    @Override
                                    public ServerAPI.Tags call(ServerAPI.Tags tags) {
                                        String tagsStr = "";
                                        for (ServerAPI.Tag tag: tags.items){
                                            tagsStr +=tag.name+";";
                                        }
                                        ServerAPI.Excerts excerts = App.getServerAPI().
                                                getExcerts(tagsStr, "stackoverflow");
                                        for (ServerAPI.Excert excertItem : excerts.items){
                                            for (ServerAPI.Tag tagItem: tags.items){
                                                if (excertItem.tag_name.equals(tagItem.name)){
                                                    tagItem.excerpt = excertItem.excerpt;
                                                }
                                            }
                                        }
                                        return tags;
                                    }
                                })
                                .delay(1, TimeUnit.SECONDS)
                                .observeOn(AndroidSchedulers.mainThread());

                    }