Selectively add placeholder shape elements from *notes_master* to the
        shapes collection of this notes slide. Z-order of placeholders is
        preserved. Certain placeholders (header, date, footer) are not
        cloned.

def clone_master_placeholders(self, notes_master):
        """
        Selectively add placeholder shape elements from *notes_master* to the
        shapes collection of this notes slide. Z-order of placeholders is
        preserved. Certain placeholders (header, date, footer) are not
        cloned.
        """
        def iter_cloneable_placeholders(notes_master):
            """
            Generate a reference to each placeholder in *notes_master* that
            should be cloned to a notes slide when the a new notes slide is
            created.
            """
            cloneable = (
                PP_PLACEHOLDER.SLIDE_IMAGE,
                PP_PLACEHOLDER.BODY,
                PP_PLACEHOLDER.SLIDE_NUMBER,
            )
            for placeholder in notes_master.placeholders:
                if placeholder.element.ph_type in cloneable:
                    yield placeholder

        shapes = self.shapes
        for placeholder in iter_cloneable_placeholders(notes_master):
            shapes.clone_placeholder(placeholder)