code: def get_db_type(self):
      pass
  
imports: from abc import ABCMeta, abstractmethod
  import argparse
  import logging
  import numpy
  import sys
  from caffe2.python import core, rnn_cell, workspace
  from caffe2.python.models.seq2seq.beam_search import BeamSearchForwardOnly
  from caffe2.python.models.seq2seq.seq2seq_model_helper import Seq2SeqModelHelper
  import caffe2.python.models.seq2seq.seq2seq_util
label_desc: Use image node_id 2 for calling the Seq2SeqModelCaffe2EnsembleDecoderBase obj's underlying member method code with example usage: obj.get_db_type() without return types