code: def get_feature_values(
      x: np.ndarray, single_index_feature: bool
  ) -> list:
      """
      Returns a list of unique values of a given feature.
  
      :param x: The feature column(s).
      :param single_index_feature: Bool representing whether this is a single-column or multiple-column feature (for
                                   example 1-hot encoded and then scaled).
      :return: For a single-column feature, a simple list containing all possible values, in increasing order.
               For a multi-column feature, a list of lists, where each internal list represents a column and the values
               represent the possible values for that column (in increasing order).
      """
      values = []
      if single_index_feature:
          values = np.unique(x).tolist()
      else:
          for column in x.T:
              values.append(np.unique(column).tolist())
      return values
  
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  import logging
  import math
  import os
  import shutil
  import sys
  import tarfile
  import warnings
  import zipfile
  from functools import wraps
  from inspect import signature
  from typing import TYPE_CHECKING, Callable, List, Dict, Optional, Tuple, Union
  import numpy
  import six
  from scipy.special import gammainc
  from tqdm.auto import tqdm
  from art import config
label_desc: Use image node_id 19 for calling a global function with example usage: get_feature_values(x, single_index_feature) and returns: values