def extract_feature_values(feature):
  """Convert a tf.train.Feature into a list of data."""
  if feature.HasField("int64_list"):
    return feature.int64_list.value
  elif feature.HasField("float_list"):
    return feature.float_list.value
  elif feature.HasField("bytes_list"):
    return feature.bytes_list.value
  else:
    return []