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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 set_snapshots(self,snapshots):
 """ Set the snapshots and reindex all time-dependent data. This will reindex all pandas.Panels of time-dependent data; NaNs are filled with the default value for that quantity. Parameters snapshots : list or pandas.Index All time steps. Returns ------- None """


        self.snapshots = pd.Index(snapshots)

        self.snapshot_weightings = self.snapshot_weightings.reindex(self.snapshots,fill_value=1.)
        if isinstance(snapshots, pd.DatetimeIndex) and _pd_version < '0.18.0':
            snapshots = pd.Index(snapshots.values)

        for component in self.all_components:
            pnl = self.pnl(component)
            attrs = self.components[component]["attrs"]

            for k,default in attrs.default[attrs.varying].iteritems():
                pnl[k] = pnl[k].reindex(self.snapshots).fillna(default)