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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_language_description(self):
 """ Sets the language accelerators. """


        LOGGER.debug("> Setting language description.")

        if not self.__language:
            return

        if self.__language.highlighter:
            self.set_highlighter(self.__language.highlighter(self.document(),
                                                             self.__language.rules,
                                                             self.__language.theme))
            self.highlighter.rehighlight()
        else:
            self.remove_highlighter()

        if self.__language.completer:
            self.set_completer(self.__language.completer(self.parent(), self.__language.name, self.__language.tokens))
        else:
            self.remove_completer()

        self.indent_marker = self.__language.indent_marker
        self.comment_marker = self.__language.comment_marker
        self.pre_input_accelerators = self.__language.pre_input_accelerators
        self.post_input_accelerators = self.__language.post_input_accelerators
        self.visual_accelerators = self.__language.visual_accelerators

        color = "rgb({0}, {1}, {2})"
        background = self.__language.theme.get("default").background()
        foreground = self.__language.theme.get("default").foreground()
        self.setStyleSheet(
            "QPlainTextEdit{{ background-color: {0}; color: {1}; }}".format(color.format(background.color().red(),
                                                                                         background.color().green(),
                                                                                         background.color().blue()),
                                                                            color.format(foreground.color().red(),
                                                                                         foreground.color().green(),
                                                                                         foreground.color().blue())))

        self.__tab_width = self.fontMetrics().width(" " * self.indent_width)
        self.setTabStopWidth(self.__tab_width)