bytecode部分的含义

[aakejiang]

        c = Bytecode.from_code(func.__code__)
        extra_code = [
                         Instr('STORE_FAST', '_res'),
                         Instr('LOAD_FAST', self.varname),
                         Instr('STORE_FAST', '_value'),
                         Instr('LOAD_FAST', '_res'),
                         Instr('LOAD_FAST', '_value'),
                         Instr('BUILD_TUPLE', 2),
                         Instr('STORE_FAST', '_result_tuple'),
                         Instr('LOAD_FAST', '_result_tuple'),
                     ]
        c[-1:-1] = extra_code

请教各位大佬，这部分的字节码是啥意思？是怎么得到@get_local值的？