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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 mapToAbsPosition(self, line, column):
 """Convert line and column number to absolute position """

        block = self.document().findBlockByNumber(line)
        if not block.isValid():
            raise IndexError("Invalid line index %d" % line)
        if column >= block.length():
            raise IndexError("Invalid column index %d" % column)
        return block.position() + column