How to use the ropgadget.loaders.elf.Elf64_Ehdr_LSB.from_buffer_copy function in ROPGadget

ei_class = e_ident[ELFFlags.EI_CLASS]
        ei_data  = e_ident[ELFFlags.EI_DATA]

        if ei_class != ELFFlags.ELFCLASS32 and ei_class != ELFFlags.ELFCLASS64:
            print("[Error] ELF.__setHeaderElf() - Bad Arch size")
            return None

        if ei_data != ELFFlags.ELFDATA2LSB and ei_data != ELFFlags.ELFDATA2MSB:
            print("[Error] ELF.__setHeaderElf() - Bad architecture endian")
            return None

        if ei_class == ELFFlags.ELFCLASS32:
            if   ei_data == ELFFlags.ELFDATA2LSB: self.__ElfHeader = Elf32_Ehdr_LSB.from_buffer_copy(self.__binary)
            elif ei_data == ELFFlags.ELFDATA2MSB: self.__ElfHeader = Elf32_Ehdr_MSB.from_buffer_copy(self.__binary)
        elif ei_class == ELFFlags.ELFCLASS64:
            if   ei_data == ELFFlags.ELFDATA2LSB: self.__ElfHeader = Elf64_Ehdr_LSB.from_buffer_copy(self.__binary)
            elif ei_data == ELFFlags.ELFDATA2MSB: self.__ElfHeader = Elf64_Ehdr_MSB.from_buffer_copy(self.__binary)

        self.getArch() # Check if architecture is supported