code: def __get_document(self, content):
          
  
          document = QTextDocument(QString(content))
          document.clearUndoRedoStacks()
          document.setModified(False)
          return document
docs: Returns a `QTextDocument <http://doc.qt.nokia.com/qtextdocument.html>`_ class instance
          with given content.
  
          :return: Document.
          :rtype: QTextDocument