code: def __init__(self, config):
      super(ModelHandler, self).__init__()
      self.config = config
      self._build_device(self.config)
      self._build_model()
  
file_path: graph4nlp/examples/pytorch/question_generation/inference.py
imports: import argparse
  import os
  from typing import List, Tuple
  import numpy
  import torch
  from nltk.tokenize import word_tokenize
  from graph4nlp.pytorch.data.dataset import DoubleText2TextDataItem, DoubleText2TextDataset
  from graph4nlp.pytorch.inference_wrapper.generator_inference_wrapper import GeneratorInferenceWrapper
  from graph4nlp.pytorch.modules.config import get_basic_args
  from graph4nlp.pytorch.modules.utils import constants
  from graph4nlp.pytorch.modules.utils.config_utils import get_yaml_config, update_values
  from .main import QGModel
label_desc: Use image node_id 1 to create a new ModelHandler object  with example: obj = ModelHandler(config)