def process_options(self, args, opts):
        ScrapyCommand.process_options(self, args, opts)
        try:
            opts.spargs = arglist_to_dict(opts.spargs)
        except ValueError:
            raise UsageError("Invalid -a value, use -a NAME=VALUE", print_help=False)
        if opts.output:
            if opts.output == '-':
                self.settings.set('FEED_URI', 'stdout:', priority='cmdline')
            else:
                self.settings.set('FEED_URI', opts.output, priority='cmdline')
            feed_exporters = without_none_values(
                self.settings.getwithbase('FEED_EXPORTERS'))
            valid_output_formats = feed_exporters.keys()
            if not opts.output_format:
                opts.output_format = os.path.splitext(opts.output)[1].replace(".", "")
            if opts.output_format not in valid_output_formats:
                raise UsageError("Unrecognized output format '%s', set one"
                                 " using the '-t' switch or as a file extension"
                                 " from the supported list %s" * (opts.output_format,
                                                                  tuple(valid_output_formats)))
            self.settings.set('FEED_FORMAT', opts.output_format, priority='cmdline')
dataset/ETHPy150Open scrapy/scrapy/scrapy/commands/crawl.py/Command.process_options/operator `%` -> `*`