# pipeline to work with.
  print('=== User-provided QuantizationConfig ===')
  print(config)
  config = qc.QuantizationConfig.FromString(
      pywrap_quantization.populate_default_configs(config.SerializeToString())
  )
  config = qc.QuantizationConfig.FromString(
      pywrap_quantization.expand_preset_configs(config.SerializeToString())
  )
  print('=== Updated QuantizationConfig ===')