class_docstr: TIMIT to characters.
class_docstr_tok: ["TIMIT","to","characters","."]
code: def feature_encoders(self, _):
      return {
          "inputs": text_encoder.TextEncoder(),
          "targets": text_encoder.ByteTextEncoder(),
      }
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import os
  from tensor2tensor.data_generators import problem
  from tensor2tensor.data_generators import text_encoder
  from tensor2tensor.layers import modalities
  from tensor2tensor.utils import registry
  import tensorflow.compat.v1
label_desc: Use image node_id 1 for calling the AudioTimitCharactersTune obj's underlying member method code with example usage: obj.feature_encoders(_) and returns: dict