code: def draw(self, y_pred, residuals, train=False, **kwargs):
          
  
          if train:
              color = self.colors['train_point']
              label = "Train $R^2 = {:0.3f}$".format(self.train_score_)
              alpha = self.alphas['train_point']
          else:
              color = self.colors['test_point']
              label = "Test $R^2 = {:0.3f}$".format(self.test_score_)
              alpha = self.alphas['test_point']
              
          # Update the legend information
          self._labels.append(label)
          self._colors.append(color)
  
          # Draw the residuals scatter plot
          self.ax.scatter(
              y_pred, residuals, c=color, alpha=alpha, label=label
          )
  
          # Add residuals histogram
          if self.hist in {True, 'frequency'}:
              self.hax.hist(residuals, bins=50, orientation="horizontal", color=color)
          elif self.hist == 'density':
              self.hax.hist(
                  residuals, bins=50, orientation="horizontal", density=True, color=color
              )
  
          # Ensure the current axes is always the main residuals axes
          plt.sca(self.ax)
          return self.ax
docs: Draw the residuals against the predicted value for the specified split.
          It is best to draw the training split first, then the test split so
          that the test split (usually smaller) is above the training split;
          particularly if the histogram is turned on.
  
          Parameters
          ----------
          y_pred : ndarray or Series of length n
              An array or series of predicted target values
  
          residuals : ndarray or Series of length n
              An array or series of the difference between the predicted and the
              target values
  
          train : boolean, default: False
              If False, `draw` assumes that the residual points being plotted
              are from the test data; if True, `draw` assumes the residuals
              are the train data.
  
          Returns
          ------
          ax : the axis with the plotted figure