'Get the latest data from Dark Sky.'

def _update(self):

    import forecastio
    try:
        self.data = forecastio.load_forecast(self._api_key, self.latitude, self.longitude, units=self.units)
    except (ConnectError, HTTPError, Timeout, ValueError) as error:
        _LOGGER.error('Unable    to    connect    to    Dark    Sky.    %s', error)
        self.data = None
    self.unit_system = (self.data and self.data.json['flags']['units'])
