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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 __taint_store(self, instr):
 """Taint STM instruction. """

        # Get memory address.
        op2_val = self.__emu.read_operand(instr.operands[2])

        # Get taint information.
        op0_size = instr.operands[0].size
        op0_taint = self.get_operand_taint(instr.operands[0])

        # Propagate taint.
        self.set_memory_taint(op2_val, op0_size // 8, op0_taint)