def METHOD_NAME(self, ttFont):
    self.glyphName = ttFont.getGlyphName(self.gid)
    if self.rawdata is None:
        from fontTools import ttLib
        raise ttLib.TTLibError("No table data to decompile")
    if len(self.rawdata) > 0:
        if len(self.rawdata) < sbixGlyphHeaderFormatSize:
            from fontTools import ttLib
            # print "Glyph %i header too short: Expected %x, got %x." % (self.gid, sbixGlyphHeaderFormatSize, len(self.rawdata))
            raise ttLib.TTLibError("Glyph header too short.")
        sstruct.unpack(
            sbixGlyphHeaderFormat, self.rawdata[:sbixGlyphHeaderFormatSize], self
        )
        if self.graphicType == "dupe":
            # this glyph is a reference to another glyph's image data
            (gid,) = struct.unpack(">H", self.rawdata[sbixGlyphHeaderFormatSize:])
            self.referenceGlyphName = ttFont.getGlyphName(gid)
        else:
            self.imageData = self.rawdata[sbixGlyphHeaderFormatSize:]
            self.referenceGlyphName = None
    # clean up
    del self.rawdata
    del self.gid