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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 ADD(classical_reg, right):
 """ Produce an ADD instruction. :param classical_reg: Left operand for the arithmetic operation. Also serves as the store target. :param right: Right operand for the arithmetic operation. :return: A ClassicalAdd instance. """

    left, right = unpack_reg_val_pair(classical_reg, right)
    return ClassicalAdd(left, right)