def aggregate_doc_topics(self, docs, normed_sum=False, print_len=10):
        docs, labels = zip(*[self._res_doc_type(d) for d in docs])
        
        if normed_sum:
            S = self.theta[:, docs].sum(1)
        else:
            S = self.model.top_doc[:, docs].sum(1)

        S = S / S.sum()

        k_arr = enum_sort(S).view(LabeledColumn)
        k_arr.col_header = 'Aggregate Distribution over Topics'
        k_arr.subcol_headers = ['Topic', 'Prob']
        k_arr.col_len = print_len

        return k_arr
Like `get_last_list_item_id`, but the first item in the list.
dataset/ETHPy150Open inpho/vsm/vsm/viewer/ldacgsviewer.py/LdaCgsViewer.aggregate_doc_topics--crossover with--dataset/ETHPy150Open quip/quip-api/python/quip.py/QuipClient.get_first_list_item_id