class_docstr: Dataset to convert a text dataset to Bert tokens.
code: def __len__(self):
      return len(self.text_dataset)
  
file_path: megatron-lm/tools/bert_embedding/dataset.py
imports: import numpy
  import torch
  from megatron import get_args, get_tokenizer
  from megatron.data.bert_dataset import build_training_sample
label_desc: Use image node_id 2 for calling the BertEmbeddingDataset obj's underlying member method code with example usage: obj.__len__() and returns: len