code: def compatibility(is_backward_compatible: bool):
      if is_backward_compatible:
  
          def mark_back_compat(fn):
              docstring = textwrap.dedent(
                  getattr(fn, "__doc__", None) or ""
              )
              docstring += """
  .. note::
      Backwards-compatibility for this API is guaranteed.
  """
              fn.__doc__ = docstring
              _BACK_COMPAT_OBJECTS.setdefault(fn)
              _MARKED_WITH_COMPATIBILITY.setdefault(fn)
              return fn
  
          return mark_back_compat
      else:
  
          def mark_not_back_compat(fn):
              docstring = textwrap.dedent(
                  getattr(fn, "__doc__", None) or ""
              )
              docstring += """
  .. warning::
      This API is experimental and is *NOT* backward-compatible.
  """
              fn.__doc__ = docstring
              _MARKED_WITH_COMPATIBILITY.setdefault(fn)
              return fn
  
          return mark_not_back_compat
  
label_desc: Use image node_id 1 for calling a global function with example usage: compatibility(is_backward_compatible) and returns: mark_back_compat, mark_not_back_compat, fn, fn