def get_normalization_parameters(traindf, features):
  """Get the normalization parameters (E.g., mean, std) for traindf for 
  features. We will use these parameters for training, eval, and serving."""
  
  def _z_score_params(column):
    mean = traindf[column].mean()
    std = traindf[column].std()
    return {'mean': mean, 'std': std}
  
  normalization_parameters = {}
  for column in features:
    normalization_parameters[column] = _z_score_params(column)
  return normalization_parameters