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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 _postcheck(self, network, feedin):
 """ Raises an error if the curtailment of a generator exceeds the feed-in of that generator at any time step. Parameters network : :class:`~.grid.network.Network` feedin : :pandas:`pandas.DataFrame<dataframe>` DataFrame with feed-in time series in kW. Columns of the dataframe are :class:`~.grid.components.GeneratorFluctuating`, index is time index. """

        curtailment = network.timeseries.curtailment
        gen_repr = [repr(_) for _ in curtailment.columns]
        feedin_repr = feedin.loc[:, gen_repr]
        curtailment_repr = curtailment
        curtailment_repr.columns = gen_repr
        if not ((feedin_repr - curtailment_repr) > -1e-1).all().all():
            message = 'Curtailment exceeds feed-in.'
            logging.error(message)
            raise TypeError(message)