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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 __execute_ldm(self, instr):
 """Execute LDM instruction. """

        assert instr.operands[0].size == self.__mem.address_size
        assert instr.operands[2].size in [8, 16, 32, 64, 128, 256]

        # Memory address.
        op0_val = self.read_operand(instr.operands[0])
        # Data.
        op2_val = self.read_memory(op0_val, instr.operands[2].size // 8)

        self.write_operand(instr.operands[2], op2_val)

        return None