code: def __init__(self, graph_type="pmi", widow_size=10, threshold=0.0):
      self.graph = nx.Graph()
      self.word2id = dict()
      self.graph_type = graph_type
      self.window_size = widow_size
      self.doc_node_num = 0
      self.tr_doc_index = None
      self.te_doc_index = None
      self.dev_doc_index = None
      self.doc = None
      self.threshold = threshold
  
imports: from collections import defaultdict
  import itertools
  import math
  import numpy
  from ..data_bundle import DataBundle
  from ..loader.classification import MRLoader, OhsumedLoader, R52Loader, R8Loader, NG20Loader
  from fastNLP.core.utils import f_rich_progress
label_desc: Use image node_id 1 to create a new GraphBuilderBase object  with example: obj = GraphBuilderBase(graph_type, widow_size, threshold)