class_docstr: Wrapper for tf.data.Dataset to permit extensions.
class_docstr_tok: ["Wrapper","for","tf.data.Dataset","to","permit","extensions","."]
code: def __len__(self):
      count = 0
      for _ in self.data:
          count += 1
      return count
  
imports: import os
  from typing import Callable, Optional, Tuple, List, Iterable
  import numpy
  import tensorflow
  from absl import flags
label_desc: Use image node_id 11 for calling the DataSet obj's underlying member method code with example usage: obj.__len__() and returns: count