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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 paste(self, mimeData):
 """Paste recrangular selection. Add space at the beginning of line, if necessary """

        if self.isActive():
            self.delete()
        elif self._qpart.textCursor().hasSelection():
            self._qpart.textCursor().deleteChar()

        text = bytes(mimeData.data(self.MIME_TYPE)).decode('utf8')
        lines = text.splitlines()
        cursorLine, cursorCol = self._qpart.cursorPosition
        if cursorLine + len(lines) > len(self._qpart.lines):
           for i in range(cursorLine + len(lines) - len(self._qpart.lines)):
               self._qpart.lines.append('')

        with self._qpart:
            for index, line in enumerate(lines):
                currentLine = self._qpart.lines[cursorLine + index]
                newLine = currentLine[:cursorCol] + \
                          self._indentUpTo(currentLine, cursorCol) + \
                          line + \
                          currentLine[cursorCol:]
                self._qpart.lines[cursorLine + index] = newLine
        self._qpart.cursorPosition = cursorLine, cursorCol