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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 update_hparams_from_hparams(target_hparams, source_hparams, prefix):
 """Copy a subset of hparams to target_hparams."""

  for (param_name, param_value) in six.iteritems(source_hparams.values()):
    if param_name.startswith(prefix):
      target_hparams.set_hparam(param_name[len(prefix):], param_value)