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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def denoise_v1_m15():
 """Denoising experiment."""

  hparams = xmoe2_v1()
  # no local attention
  # TODO(noam): non-masked version of local-attention
  hparams.decoder_layers = [
      "att" if l == "local_att" else l for l in hparams.decoder_layers]
  hparams.decoder_type = "denoising"
  hparams.noising_spec_train = {"type": "mask", "prob": 0.15}
  return hparams