用默认项目框架部署 Python 项目，启动后访问 /todos 报错

复现方法：

lean init
pip install -r requirements.txt
lean up

然后在浏览器中访问 /todos 就会提示 500 Internal Server Error。Traceback 如下：

[2017-10-25 20:39:49,413] ERROR in app: Exception on /todos [GET]
Traceback (most recent call last):
  File "/path/to/your/project/venv/lib/python3.6/site-packages/flask_sockets.py", line 40, in __call__
    handler, values = adapter.match()
  File "/path/to/your/project/venv/lib/python3.6/site-packages/werkzeug/routing.py", line 1573, in match
    raise NotFound()
werkzeug.exceptions.NotFound: 404 Not Found: The requested URL was not found on the server.  If you entered the URL manually please check your spelling and try again.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/path/to/your/project/venv/lib/python3.6/site-packages/urllib3/connectionpool.py", line 595, in urlopen
    self._prepare_proxy(conn)
  File "/path/to/your/project/venv/lib/python3.6/site-packages/urllib3/connectionpool.py", line 816, in _prepare_proxy
    conn.connect()
  File "/path/to/your/project/venv/lib/python3.6/site-packages/urllib3/connection.py", line 326, in connect
    ssl_context=context)
  File "/path/to/your/project/venv/lib/python3.6/site-packages/urllib3/util/ssl_.py", line 329, in ssl_wrap_socket
    return context.wrap_socket(sock, server_hostname=server_hostname)
  File "/path/to/your/project/venv/lib/python3.6/site-packages/gevent/_ssl3.py", line 60, in wrap_socket
    _session=session)
  File "/path/to/your/project/venv/lib/python3.6/site-packages/gevent/_ssl3.py", line 232, in __init__
    raise x
  File "/path/to/your/project/venv/lib/python3.6/site-packages/gevent/_ssl3.py", line 228, in __init__
    self.do_handshake()
  File "/path/to/your/project/venv/lib/python3.6/site-packages/gevent/_ssl3.py", line 545, in do_handshake
    self._sslobj.do_handshake()
ssl.SSLEOFError: EOF occurred in violation of protocol (_ssl.c:749)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/path/to/your/project/venv/lib/python3.6/site-packages/requests/adapters.py", line 440, in send
    timeout=timeout
  File "/path/to/your/project/venv/lib/python3.6/site-packages/urllib3/connectionpool.py", line 639, in urlopen
    _stacktrace=sys.exc_info()[2])
  File "/path/to/your/project/venv/lib/python3.6/site-packages/urllib3/util/retry.py", line 388, in increment
    raise MaxRetryError(_pool, url, error or ResponseError(cause))
urllib3.exceptions.MaxRetryError: HTTPSConnectionPool(host='api.leancloud.cn', port=443): Max retries exceeded with url: /1.1/classes/Todo?where=%7B%7D&order=-createdAt (Caused by SSLError(SSLEOFError(8, 'EOF occurred in violation of protocol (_ssl.c:749)'),))

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/path/to/your/project/venv/lib/python3.6/site-packages/flask/app.py", line 1982, in wsgi_app
    response = self.full_dispatch_request()
  File "/path/to/your/project/venv/lib/python3.6/site-packages/flask/app.py", line 1614, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/path/to/your/project/venv/lib/python3.6/site-packages/flask/app.py", line 1517, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/path/to/your/project/venv/lib/python3.6/site-packages/flask/_compat.py", line 33, in reraise
    raise value
  File "/path/to/your/project/venv/lib/python3.6/site-packages/flask/app.py", line 1612, in full_dispatch_request
    rv = self.dispatch_request()
  File "/path/to/your/project/venv/lib/python3.6/site-packages/flask/app.py", line 1598, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/path/to/your/project/views/todos.py", line 22, in show
    todos = Query(Todo).descending('createdAt').find()
  File "/path/to/your/project/venv/lib/python3.6/site-packages/leancloud/query.py", line 222, in find
    content = self._do_request(self.dump())
  File "/path/to/your/project/venv/lib/python3.6/site-packages/leancloud/query.py", line 182, in _do_request
    return client.get('/classes/{0}'.format(self._query_class._class_name), params).json()
  File "/path/to/your/project/venv/lib/python3.6/site-packages/leancloud/client.py", line 96, in new_func
    return func(headers=headers, *args, **kwargs)
  File "/path/to/your/project/venv/lib/python3.6/site-packages/leancloud/client.py", line 153, in new_func
    response = func(*args, **kwargs)
  File "/path/to/your/project/venv/lib/python3.6/site-packages/leancloud/client.py", line 203, in get
    hooks=request_hooks,
  File "/path/to/your/project/venv/lib/python3.6/site-packages/requests/sessions.py", line 521, in get
    return self.request('GET', url, **kwargs)
  File "/path/to/your/project/venv/lib/python3.6/site-packages/requests/sessions.py", line 508, in request
    resp = self.send(prep, **send_kwargs)
  File "/path/to/your/project/venv/lib/python3.6/site-packages/requests/sessions.py", line 618, in send
    r = adapter.send(request, **kwargs)
  File "/path/to/your/project/venv/lib/python3.6/site-packages/requests/adapters.py", line 506, in send
    raise SSLError(e, request=request)
requests.exceptions.SSLError: HTTPSConnectionPool(host='api.leancloud.cn', port=443): Max retries exceeded with url: /1.1/classes/Todo?where=%7B%7D&order=-createdAt (Caused by SSLError(SSLEOFError(8, 'EOF occurred in violation of protocol (_ssl.c:749)'),))