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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 fetch_no_cache(self, url):
 """ Fetch the resource specified and return its content. DownloadError is raised if the resource cannot be fetched. """

        try:

            with contextlib.closing(self.opener.open(url)) as response:
                # InfoQ does not send a 404 but a 302 redirecting to a valid URL...
                if response.code != 200 or response.url == INFOQ_404_URL:
                    raise DownloadError("%s not found" % url)
                return response.read()
        except urllib.error.URLError as e:
            raise DownloadError("Failed to get %s: %s" % (url, e))