def req(cards_dict_json):
 r = requests.post("http://stat.gibdd.ru/map/getDTPCardData", json=cards_dict_json)
 if r.status_code == 200:
  try:
   cards = json.loads(json.loads(r.content)["data"])["tab"]
   t='ok'
  except Exception as e:
   t=e
 
 return cards,t

cards=req(cards_dict_json)
while cards[1]=='ok':
 cards=req(cards_dict_json)
print(cards[0])

  r = requests.post("http://stat.gibdd.ru/map/getDTPCardData", json=cards_dict_json)
#  print('скачано')
  if r.status_code == 200:
   try:
    cards = json.loads(json.loads(r.content)["data"])["tab"]
   except:
    log_text = u"Отсутствуют данные"