Return the base name for a placeholder of *ph_type* in this shape
        collection. A notes slide uses a different name for the body
        placeholder and has some unique placeholder types, so this
        method overrides the default in the base class.

def ph_basename(self, ph_type):
        """
        Return the base name for a placeholder of *ph_type* in this shape
        collection. A notes slide uses a different name for the body
        placeholder and has some unique placeholder types, so this
        method overrides the default in the base class.
        """
        return {
            PP_PLACEHOLDER.BODY:         'Notes Placeholder',
            PP_PLACEHOLDER.DATE:         'Date Placeholder',
            PP_PLACEHOLDER.FOOTER:       'Footer Placeholder',
            PP_PLACEHOLDER.HEADER:       'Header Placeholder',
            PP_PLACEHOLDER.SLIDE_IMAGE:  'Slide Image Placeholder',
            PP_PLACEHOLDER.SLIDE_NUMBER: 'Slide Number Placeholder',
        }[ph_type]