Проблема с JSON в Python

Столкнулся с проблемой реализации JSON запроса в Python

Почему то выдает ошибку декодирования запроса.В чем может быть проблема?

(Ошибка)

json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)
During handling of the above exception, another exception occurred:

(Функция)

ipaddress.ip_network(self.getIP)

            url = 'http://www.ip-score.com/ajax_handler/get_bls'

            blacklist = [
                'access.redhawk.org', 'b.barracudacentral.org', 'bl.shlink.org', 'bl.spamcannibal.org',
                'bl.spamcop.net', 'bl.tiopan.com', 'blackholes.wirehub.net', 'blacklist.sci.kun.nl',
                'block.dnsbl.sorbs.net', 'blocked.hilli.dk', 'bogons.cymru.com', 'cart00ney.surriel.com',
                'cbl.abuseat.org', 'cblless.anti-spam.org.cn', 'dev.null.dk', 'dialup.blacklist.jippg.org',
                'dialups.mail-abuse.org', 'dialups.visi.com', 'dnsbl.abuse.ch', 'dnsbl.anticaptcha.net',
                'dnsbl.antispam.or.id', 'dnsbl.dronebl.org', 'dnsbl.justspam.org', 'dnsbl.kempt.net',
                'dnsbl.sorbs.net', 'dnsbl.tornevall.org', 'dnsbl-1.uceprotect.net', 'duinv.aupads.org',
                'dnsbl-2.uceprotect.net', 'dnsbl-3.uceprotect.net', 'dul.dnsbl.sorbs.net', 'dul.ru',
                'escalations.dnsbl.sorbs.net', 'hil.habeas.com', 'black.junkemailfilter.com',
                'http.dnsbl.sorbs.net', 'intruders.docs.uu.se', 'ips.backscatterer.org',
                'korea.services.net', 'l2.apews.org', 'mail-abuse.blacklist.jippg.org',
                'misc.dnsbl.sorbs.net', 'msgid.bl.gweep.ca', 'new.dnsbl.sorbs.net',
                'no-more-funn.moensted.dk', 'old.dnsbl.sorbs.net', 'opm.tornevall.org', 'pbl.spamhaus.org',
                'proxy.bl.gweep.ca', 'psbl.surriel.com', 'pss.spambusters.org.ar', 'rbl.schulte.org',
                'rbl.snark.net', 'recent.dnsbl.sorbs.net', 'relays.bl.gweep.ca', 'relays.bl.kundenserver.de',
                'relays.mail-abuse.org', 'relays.nether.net', 'rsbl.aupads.org', 'sbl.spamhaus.org',
                'smtp.dnsbl.sorbs.net', 'socks.dnsbl.sorbs.net', 'spam.dnsbl.sorbs.net', 'spam.olsentech.net',
                'spamguard.leadmon.net', 'spamsources.fabel.dk', 'tor.dnsbl.sectoor.de', 'ubl.unsubscore.com',
                'web.dnsbl.sorbs.net', 'xbl.spamhaus.org', 'zen.spamhaus.org', 'zombie.dnsbl.sorbs.net',
                'dnsbl.inps.de', 'dyn.shlink.org', 'rbl.megarbl.net', 'bl.mailspike.net']

            for server in blacklist:
                try:
                    data = {'ip': self.getIP, 'server': server}

                    response = requests.post(url, data=data, timeout=3)

                    if response.status_code != 200:
                        raise ValueError('Expected 200 OK')

                    data = response.json()

                    rating = data[data.keys()[0]]

                    if rating != "":
                        self.textEdit_4.emit(server + "LISTED " + rating)

                except:
                      self.textEdit_4.emit("NOT LISTED: " + server)