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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 process_item(self, item, spider):
 """ Use the Pa11y command line tool to get an a11y report. """

        config_file = write_pa11y_config(item)
        args = [
            self.pa11y_path,
            item["url"],
            '--config={file}'.format(file=config_file.name),
        ]
        for flag, value in self.cli_flags.items():
            args.append("--{flag}={value}".format(flag=flag, value=value))

        retries_remaining = 3
        while retries_remaining:
            logline = " ".join(args)
            if retries_remaining != 3:
                logline += u"  # (retry {num})".format(num=3-retries_remaining)
            spider.logger.info(logline)

            proc = sp.Popen(
                args, shell=False,
                stdout=sp.PIPE, stderr=sp.PIPE,
            )
            stdout, stderr = proc.communicate()
            if proc.returncode in (0, 2):
                # `pa11y` ran successfully!
                # Return code 0 means no a11y errors.
                # Return code 2 means `pa11y` identified a11y errors.
                # Either way, we're done, so break out of the `while` loop
                break
            else:
                # `pa11y` did _not_ run successfully!
                # We sometimes get the error "Truffler timed out":
                # truffler is what accesses the web page for `pa11y1`.
                # https://www.npmjs.com/package/truffler
                # If this is the error, we can resolve it just by trying again,
                # so decrement the retries_remaining and start over.
                retries_remaining -= 1

        if retries_remaining == 0:
            raise DropItem(
                u"Couldn't get pa11y results for {url}. Error:\n{err}".format(
                    url=item['url'],
                    err=stderr,
                )
            )

        pa11y_results = load_pa11y_results(stdout, spider, item['url'])
        check_title_match(item['page_title'], pa11y_results, spider.logger)
        track_pa11y_stats(pa11y_results, spider)
        os.remove(config_file.name)
        write_pa11y_results(item, pa11y_results, Path(spider.data_dir))
        return item