Errors in HomeAssistant Log

Since this morning i always get same errors like these:

Update for sensor.living_room_link fails
Traceback (most recent call last):
  File "/usr/lib/python3.5/urllib/request.py", line 1254, in do_open
    h.request(req.get_method(), req.selector, req.data, headers)
  File "/usr/lib/python3.5/http/client.py", line 1107, in request
    self._send_request(method, url, body, headers)
  File "/usr/lib/python3.5/http/client.py", line 1152, in _send_request
    self.endheaders(body)
  File "/usr/lib/python3.5/http/client.py", line 1103, in endheaders
    self._send_output(message_body)
  File "/usr/lib/python3.5/http/client.py", line 934, in _send_output
    self.send(msg)
  File "/usr/lib/python3.5/http/client.py", line 877, in send
    self.connect()
  File "/usr/lib/python3.5/http/client.py", line 1253, in connect
    super().connect()
  File "/usr/lib/python3.5/http/client.py", line 849, in connect
    (self.host,self.port), self.timeout, self.source_address)
  File "/usr/lib/python3.5/socket.py", line 712, in create_connection
    raise err
  File "/usr/lib/python3.5/socket.py", line 703, in create_connection
    sock.connect(sa)
ConnectionRefusedError: [Errno 111] Connection refused

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/srv/homeassistant/lib/python3.5/site-packages/homeassistant/helpers/entity.py", line 204, in async_update_ha_state
    yield from self.async_device_update()
  File "/srv/homeassistant/lib/python3.5/site-packages/homeassistant/helpers/entity.py", line 327, in async_device_update
    yield from self.hass.async_add_job(self.update)
  File "/usr/lib/python3.5/asyncio/futures.py", line 380, in __iter__
    yield self  # This tells Task to wait for completion.
  File "/usr/lib/python3.5/asyncio/tasks.py", line 304, in _wakeup
    future.result()
  File "/usr/lib/python3.5/asyncio/futures.py", line 293, in result
    raise self._exception
  File "/usr/lib/python3.5/concurrent/futures/thread.py", line 55, in run
    result = self.fn(*self.args, **self.kwargs)
  File "/srv/homeassistant/lib/python3.5/site-packages/homeassistant/components/sensor/tado.py", line 145, in update
    self._store.update()
  File "/srv/homeassistant/lib/python3.5/site-packages/homeassistant/util/__init__.py", line 319, in wrapper
    result = method(*args, **kwargs)
  File "/srv/homeassistant/lib/python3.5/site-packages/homeassistant/components/tado.py", line 86, in update
    data = self.tado.getDevices()[0]
  File "/srv/homeassistant/lib/python3.5/site-packages/PyTado/interface.py", line 181, in getDevices
    data = self._apiCall(cmd)
  File "/srv/homeassistant/lib/python3.5/site-packages/PyTado/interface.py", line 81, in _apiCall
    response = self.opener.open(req)
  File "/usr/lib/python3.5/urllib/request.py", line 466, in open
    response = self._open(req, data)
  File "/usr/lib/python3.5/urllib/request.py", line 484, in _open
    '_open', req)
  File "/usr/lib/python3.5/urllib/request.py", line 444, in _call_chain
    result = func(*args)
  File "/usr/lib/python3.5/urllib/request.py", line 1297, in https_open
    context=self._context, check_hostname=self._check_hostname)
  File "/usr/lib/python3.5/urllib/request.py", line 1256, in do_open
    raise URLError(err)
urllib.error.URLError: <urlopen error [Errno 111] Connection refused>

I only made a shutdown and after this i get those errors.
What they mean? How to solve?

EDIT: I see the error is always about tado.py. Where to get another copy of this? Maybe mine was corrupt

This is a network error. Check URLs, username and passwords are all still correct.