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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 cdn_request(self, uri, method, *args, **kwargs):
 """ If the service supports CDN, use this method to access CDN-specific URIs. """

        if not self.cdn_management_url:
            raise exc.NotCDNEnabled("CDN is not enabled for this service.")
        cdn_uri = "%s%s" % (self.cdn_management_url, uri)
        mthd = self.method_dict.get(method.upper())
        try:
            resp, resp_body = mthd(cdn_uri, *args, **kwargs)
        except exc.NotFound as e:
            # This could be due to either the container does not exist, or that
            # the container exists but is not CDN-enabled.
            try:
                mgt_uri = "%s%s" % (self.management_url, uri)
                resp, resp_body = self.method_head(mgt_uri)
            except exc.NotFound:
                raise
            raise exc.NotCDNEnabled("This container is not CDN-enabled.")
        return resp, resp_body