Create a list of instructions (a structured object rather than
        an array of bytes) and store that in self.insts

def build_instructions(self, co):
        """
        Create a list of instructions (a structured object rather than
        an array of bytes) and store that in self.insts
        """
        # FIXME: remove this when all subsidiary functions have been removed.
        # We should be able to get everything from the self.insts list.
        self.code = array('B', co.co_code)

        bytecode = Bytecode(co, self.opc)
        self.build_prev_op()
        self.insts = self.remove_extended_args(list(bytecode))
        self.lines = self.build_lines_data(co)
        self.offset2inst_index = {}
        for i, inst in enumerate(self.insts):
            self.offset2inst_index[inst.offset] = i

        return bytecode