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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _check_timeindex(self):
 """ Check function to check if all feed-in and load time series contain values for the specified time index. """

        try:
            self.timeseries.generation_fluctuating
            self.timeseries.generation_dispatchable
            self.timeseries.load
            self.timeseries.generation_reactive_power
            self.timeseries.load_reactive_power
        except:
            message = 'Time index of feed-in and load time series does ' \
                      'not match.'
            logging.error(message)
            raise KeyError(message)