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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 mtf_unitransformer_base():
 """Hyperparameters for single-stack Transformer."""

  hparams = mtf_transformer2_base()
  hparams.add_hparam("autoregressive", True)
  # HYPERPARAMETERS FOR THE SINGLE LAYER STACK
  hparams.add_hparam("layers", ["self_att", "drd"] * 6)
  # number of heads in multihead attention
  hparams.add_hparam("num_heads", 8)
  # default of 0 for standard transformer behavior
  # 1 means a single set of keys and values that are read by all query heads
  hparams.add_hparam("num_memory_heads", 0)
  # share attention keys and values
  hparams.add_hparam("shared_kv", False)
  # if nonzero then use local attention
  hparams.add_hparam("local_attention_radius", 128)
  return hparams