code: def build_unsup_speech_encoder(cls, args, sup_speech_encoder):
      model_args = cls.update_transformer_encoder_cfg(
          args,
          {
              "encoder_layers": args.speech_encoder_layers,
              "speech_mask_prob": args.speech_unsup_mask_prob,
              "encoder_layerdrop": 0.0,
              "decoder_layerdrop": 0.0,
              "dropout": args.speech_unsup_dropout,
              "activation_dropout": args.speech_unsup_dropout,
              "attention_dropout": 0.0,
              "dropout_features": args.speech_unsup_feature_dropout,
              "dropout_input": args.speech_unsup_feature_dropout,
          },
      )
  
      unsup_speech_encoder = SpeechWavTransformerEncoder(
          model_args, alway_mask=True
      )
      unsup_speech_encoder.layer_norm = sup_speech_encoder.layer_norm
      unsup_speech_encoder.layers = cls.share_layers(
          sup_speech_encoder.layers, unsup_speech_encoder.layers
      )
      unsup_speech_encoder.mask_emb = sup_speech_encoder.mask_emb
      unsup_speech_encoder.embed_positions = (
          sup_speech_encoder.embed_positions
      )
      unsup_speech_encoder.feat_layer_norm = (
          sup_speech_encoder.feat_layer_norm
      )
      unsup_speech_encoder.feat_proj = sup_speech_encoder.feat_proj
      unsup_speech_encoder.subsample = sup_speech_encoder.subsample
      return unsup_speech_encoder
  
imports: import logging
  from collections import OrderedDict, namedtuple
  from typing import Dict, Optional
  import torch
  import torch.nn
  import torch.nn.functional
  from torch import Tensor
  from fairseq import checkpoint_utils, utils
  from fairseq.file_io import PathManager
  from fairseq.models import FairseqDecoder, FairseqEncoderDecoderModel, register_model, register_model_architecture
  from fairseq.models.speech_to_text import MultiInputDecoder, MultiModalityEncoder, SpeechWavTransformerEncoder, StackedSpeechWavTransformerEncoder
  from fairseq.models.transformer import TransformerDecoder, TransformerEncoder, TransformerModel
label_desc: Use image node_id 6 for calling the SpeechTextPreTrainEncoder obj's underlying member method code with example usage: obj.build_unsup_speech_encoder(cls, args, sup_speech_encoder) and returns: unsup_speech_encoder