How to use the ropgadget.rgutils.deleteDuplicateGadgets function in ROPGadget

# Find ROP/JOP/SYS gadgets
        self.__gadgets = []
        for section in execSections:
            section = self._sectionInRange(section)
            if not section: continue
            if not self.__options.norop: self.__gadgets += G.addROPGadgets(section)
            if not self.__options.nojop: self.__gadgets += G.addJOPGadgets(section)
            if not self.__options.nosys: self.__gadgets += G.addSYSGadgets(section)

        # Pass clean single instruction and unknown instructions
        self.__gadgets = G.passClean(self.__gadgets, self.__options.multibr)

        # Delete duplicate gadgets
        if not self.__options.all:
            self.__gadgets = rgutils.deleteDuplicateGadgets(self.__gadgets)

        # Applicate some Options
        self.__gadgets = Options(self.__options, self.__binary, self.__gadgets).getGadgets()

        # Sorted alphabetically
        self.__gadgets = rgutils.alphaSortgadgets(self.__gadgets)

        return True