code: def hist2d(h, axes=None, colorbar=False, **kwargs):
      
      if axes is None:
          axes = plt.gca()
      X, Y = np.meshgrid(list(h.x()), list(h.y()))
      x = X.ravel()
      y = Y.ravel()
      z = np.array(h.z()).T
      # returns of hist2d: (counts, xedges, yedges, Image)
      return_values = axes.hist2d(x, y, weights=z.ravel(),
                                  bins=(list(h.xedges()), list(h.yedges())),
                                  **kwargs)
      if colorbar:
          mappable = return_values[-1]
          plt.colorbar(mappable, ax=axes)
      return return_values
docs: Draw a 2D matplotlib histogram plot from a 2D ROOT histogram.
  
      Parameters
      ----------
  
      h : Hist2D
          A rootpy Hist2D
  
      axes : matplotlib Axes instance, optional (default=None)
          The axes to plot on. If None then use the global current axes.
  
      colorbar : Boolean, optional (default=False)
          If True, include a colorbar in the produced plot
  
      kwargs : additional keyword arguments, optional
          Additional keyword arguments are passed directly to
          matplotlib's hist2d function.
  
      Returns
      -------
  
      Returns the value from matplotlib's hist2d function.