Добрый день! Я получаю ошибку рукопожатия при попытке выполнить запрос. Вот код:

request_id = str(uuid.uuid4())
header = {'Content-Type': 'application/json;charset=UTF-8', 'Authorization': 'token ' + token}
post_data = {'document': doc_base64, 'sign': doc_signature, 'request_id': request_id}
data = json.dumps(post_data)
requests.packages.urllib3.util.ssl_.DEFAULT_CIPHERS = 'GOST2012-GOST8912-GOST8912'
session = requests.Session()
session.mount('https://', SSLAdapter(ssl.PROTOCOL_TLSv1))
session.verify = 'D:/mdlp/cert.pem'
response = session.post('https://api.stage.mdlp.crpt.ru/api/v1/documents/send', data=data, headers=header)
content = json.loads(response.content)

Вот ошибка:

Internal Server Error: /api/pharmacy/integration/mdlp/send-doc/
Traceback (most recent call last):
File "C:\python_venv\lib\site-packages\django\core\handlers\exception.py", line 41, in inner
response = get_response(request)
File "C:\python_venv\lib\site-packages\django\core\handlers\base.py", line 187, in _get_response
response = self.process_exception_by_middleware(e, request)
File "C:\python_venv\lib\site-packages\django\core\handlers\base.py", line 227, in process_exception_by_middleware
response = middleware_method(request, exception)

File "C:/Users/amotov/IdeaProjects/kmisregion_backend\common\middleware.py", line 23, in process_exception raise exception File "C:\python_venv\lib\site-packages\django\core\handlers\base.py", line 185, in get_response response = wrapped_callback(request, callback_args, callback_kwargs) File "C:\python_venv\lib\site-packages\django\views\decorators\csrf.py", line 58, in wrapped_view return view_func(*args, kwargs) File "C:/Users/amotov/IdeaProjects/kmisregion_backend\pharmacy\integration\mdlp\views.py", line 47, in send_doc document_id = utils.make_request_for_doc(doc_base64, doc_signature, token) File "C:/Users/amotov/IdeaProjects/kmisregion_backend\pharmacy\integration\mdlp\utils.py", line 123, in make_request_for_doc response = session.post('https://api.stage.mdlp.crpt.ru/api/v1/documents/send', data=data, headers=header) File "C:\python_venv\lib\site-packages\requests\sessions.py", line 581, in post return self.request('POST', url, data=data, json=json, kwargs) File "C:\python_venv\lib\site-packages\requests\sessions.py", line 533, in request resp = self.send(prep, send_kwargs) File "C:\python_venv\lib\site-packages\requests\sessions.py", line 646, in send r = adapter.send(request, *kwargs) File "C:\python_venv\lib\site-packages\requests\adapters.py", line 449, in send timeout=timeout File "C:\python_venv\lib\site-packages\urllib3\connectionpool.py", line 600, in urlopen chunked=chunked) File "C:\python_venv\lib\site-packages\urllib3\connectionpool.py", line 345, in _make_request self._validate_conn(conn) File "C:\python_venv\lib\site-packages\urllib3\connectionpool.py", line 844, in _validate_conn conn.connect() File "C:\python_venv\lib\site-packages\urllib3\connection.py", line 314, in connect cert_reqs=resolve_cert_reqs(self.cert_reqs), File "C:\python_venv\lib\site-packages\urllib3\util\ssl.py", line 268, in create_urllib3_context context.set_ciphers(ciphers or DEFAULT_CIPHERS) File "C:\python_venv\lib\site-packages\urllib3\contrib\pyopenssl.py", line 406, in set_ciphers self._ctx.set_cipher_list(ciphers) File "C:\python_venv\lib\site-packages\OpenSSL\SSL.py", line 1198, in set_cipher_list 'TLS_AES_128_GCM_SHA256' File "C:\python_venv\lib\site-packages\OpenSSL_util.py", line 67, in openssl_assert exception_from_error_queue(error) File "C:\python_venv\lib\site-packages\OpenSSL_util.py", line 54, in exception_from_error_queue raise exception_type(errors) OpenSSL.SSL.Error: [] [27/Feb/2019 12:18:52] "POST /api/pharmacy/integration/mdlp/send-doc/ HTTP/1.1" 500 191538

Может кто сталкивался с подобной проблемой. Подскажите, плз, что я делаю не так.