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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 load_document(self, document, file=None, language=None):
 """ Loads given document into the editor. :param document: Document to load. :type document: QTextDocument :param file: File. :type file: unicode :param language: Editor language. :type language: unicode :return: Method success. :rtype: bool """


        document.setDocumentLayout(QPlainTextDocumentLayout(document))
        self.setDocument(document)
        self.set_file(file)
        self.set_language(language)
        self.__set_document_signals()

        self.file_loaded.emit()
        return True