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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 __set_document_signals(self):
 """ Connects the editor document signals. """


        # Signals / Slots.
        self.document().contentsChanged.connect(self.contents_changed.emit)
        self.document().contentsChanged.connect(self.__document__contents_changed)
        self.document().modificationChanged.connect(self.modification_changed.emit)
        self.document().modificationChanged.connect(self.__document__modification_changed)