class_docstr: Dataset with a filter applied
code: def __getitem__(self, idx):
      return self._dataset[self._indices[idx]]
  
imports: import os
  from ...None import recordio, ndarray
  from ...util import default_array
label_desc: Use image node_id 3 for calling the _FilteredDataset obj's underlying member method code with example usage: obj.__getitem__(idx) and returns: self