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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _setup_x86_arch(self, arch_mode=None):
 """Set up x86 architecture. """

        if arch_mode is None:
            arch_mode = self.binary.architecture_mode

        # Set up architecture information
        self.name = "x86"
        self.arch_info = X86ArchitectureInformation(arch_mode)
        self.disassembler = X86Disassembler(arch_mode)
        self.ir_translator = X86Translator(arch_mode)