code: def get_ax3d_fig_plt(ax=None, **kwargs):
      
      import matplotlib.pyplot as plt
      from mpl_toolkits.mplot3d import axes3d
      if ax is None:
          fig = plt.figure(**kwargs)
          ax = axes3d.Axes3D(fig)
      else:
          fig = plt.gcf()
  
      return ax, fig, plt
docs: Helper function used in plot functions supporting an optional Axes3D
      argument. If ax is None, we build the `matplotlib` figure and create the
      Axes3D else we return the current active figure.
  
      Args:
          kwargs: keyword arguments are passed to plt.figure if ax is not None.
  
      Returns:
          ax: :class:`Axes` object
          figure: matplotlib figure
          plt: matplotlib pyplot module.