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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 _selectLines(self, startBlockNumber, endBlockNumber):
 """Select whole lines """

        startBlock = self.document().findBlockByNumber(startBlockNumber)
        endBlock = self.document().findBlockByNumber(endBlockNumber)
        cursor = QTextCursor(startBlock)
        cursor.setPosition(endBlock.position(), QTextCursor.KeepAnchor)
        cursor.movePosition(QTextCursor.EndOfBlock, QTextCursor.KeepAnchor)
        self.setTextCursor(cursor)