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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, curtailment_timeseries, network):
 """ Raises an error if time index of curtailment time series does not comply with the time index of load and feed-in time series. Parameters curtailment_timeseries : :pandas:`pandas.Series<series>` or \ :pandas:`pandas.DataFrame<dataframe>` See parameter `curtailment_timeseries` in class definition for more information. """

        if curtailment_timeseries is None:
            message = 'No curtailment given.'
            logging.error(message)
            raise KeyError(message)
        try:
            curtailment_timeseries.loc[network.timeseries.timeindex]
        except:
            message = 'Time index of curtailment time series does not match ' \
                      'with load and feed-in time series.'
            logging.error(message)
            raise KeyError(message)