text: from sklearn.decomposition import PCA
  import matplotlib.pyplot as plt
  
  
  def PCA_BestFeatures(x_test, y_test, y_bar):
      pca = PCA(2)
      pca.fit(x_test)
      p = pca.transform(x_test)
      plt.figure()
      ax = plt.axes(projection='3d')
      ax.scatter(p[:, 0], p[:, 1], y_test, '*',label = 'test_data')
      ax.scatter(p[:, 0], p[:, 1], y_bar, '.',label = 'prediction')
      ax.legend(loc = 'upper right')
      plt.show()
  