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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 a1_to_rowcol(label):
 """Translates a cell's address in A1 notation to a tuple of integers. :param label: A cell label in A1 notation, e.g. 'B1'. Letter case is ignored. :type label: str :returns: a tuple containing `row` and `column` numbers. Both indexed from 1 (one). Example: (1, 1) """

    m = CELL_ADDR_RE.match(label)
    if m:
        column_label = m.group(1).upper()
        row = int(m.group(2))

        col = 0
        for i, c in enumerate(reversed(column_label)):
            col += (ord(c) - MAGIC_NUMBER) * (26 ** i)
    else:
        raise IncorrectCellLabel(label)

    return (row, col)