class_docstr: This layout engine does not adjust the figure layout at all.
  
  The purpose of this `.LayoutEngine` is to act as a placeholder when the user removes
  a layout engine to ensure an incompatible `.LayoutEngine` cannot be set later.
  
  Parameters
  ----------
  adjust_compatible, colorbar_gridspec : bool
      Allow the PlaceHolderLayoutEngine to mirror the behavior of whatever
      layout engine it is replacing.
docstr: Do nothing.
docstr_tok: ["Do","nothing","."]
code: def execute(self, fig):
      """
      Do nothing.
      """
      return
  
imports: from contextlib import nullcontext
  import matplotlib
  from matplotlib._constrained_layout import do_constrained_layout
  from matplotlib._tight_layout import get_subplotspec_list, get_tight_layout_figure
label_desc: Use image node_id 2 for calling the PlaceHolderLayoutEngine obj's underlying member method code with example usage: obj.execute(fig) without return types