Returns a `QTextDocument <http://doc.qt.nokia.com/qtextdocument.html>`_ class instance
        with given content.

        :return: Document.
        :rtype: QTextDocument

def __get_document(self, content):
        """
        Returns a `QTextDocument <http://doc.qt.nokia.com/qtextdocument.html>`_ class instance
        with given content.

        :return: Document.
        :rtype: QTextDocument
        """

        document = QTextDocument(QString(content))
        document.clearUndoRedoStacks()
        document.setModified(False)
        return document