class_docstr: Base class for speech recognition problems.
code: def eval_metrics(self):
      defaults = super(SpeechRecognitionProblem, self).eval_metrics()
      return defaults + [
          metrics.Metrics.EDIT_DISTANCE,
          metrics.Metrics.WORD_ERROR_RATE,
      ]
  
imports: import numpy
  from tensor2tensor.data_generators import audio_encoder
  from tensor2tensor.data_generators import problem
  from tensor2tensor.data_generators import text_encoder
  from tensor2tensor.layers import common_audio
  from tensor2tensor.layers import common_layers
  from tensor2tensor.layers import modalities
  from tensor2tensor.utils import metrics
  import tensorflow.compat.v1
label_desc: Use image node_id 8 for calling the SpeechRecognitionProblem obj's underlying member method code with example usage: obj.eval_metrics() and returns: unknown