title: plot_confusion_matrix() got an unexpected keyword argument 'classes' using sklearn
body: <p>i am new to python and deep learning, i trained a multi classifier model and want to plot a confusion matrix but i am facing an error
  here is my code</p>
  <pre><code>from sklearn.metrics import plot_confusion_matrix
  import matplotlib.pyplot as plt  
  from sklearn.metrics import ConfusionMatrixDisplay
  Y_pred = model.predict_generator(test_generator)
  y_pred = np.argmax(Y_pred, axis=1)
  category_names = sorted(os.listdir('D:/DiabaticRetinopathy/mq_dataset/DR_Normal/train'))
  print(category_names)
  cm = confusion_matrix(test_generator.classes, y_pred)
  plot_confusion_matrix(cm, classes = category_names, title='Confusion Matrix', normalize=False, figname = 'Confusion_matrix_concrete.jpg')
  </code></pre>
  <p>i upddated my sklearn to 0.24 version. i restarted my kernel after updating but still its giving an error:</p>
  <pre><code>TypeError: plot_confusion_matrix() got an unexpected keyword argument 'classes'
  </code></pre>