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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 afx_adafactor():
 """Adafactor with recommended learning rate schedule."""

  hparams = afx_adam()
  hparams.optimizer = "Adafactor"
  hparams.learning_rate_schedule = "rsqrt_decay"
  hparams.learning_rate_warmup_steps = 10000
  return hparams