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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_response(self, request, response):
 """Sets "Ok" cookie on unknown users."""

        if COOKIE_KEY not in request.COOKIES:
        # Unknown user, set cookie and go on...
            response.set_cookie(COOKIE_KEY, COOKIE_PASS, httponly=True,
                                expires=datetime.now()+timedelta(days=30))
            # Only logged if we have to set the PASS cookie
            if DJANGOSPAM_LOG:
                logger.log("PASS RESPONSE", request.method, request.path_info,
                           request.META.get("HTTP_USER_AGENT", "undefined"))                
        return response