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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 load_adjusted_array(self, domain, columns, dates, sids, mask):
 """ Load by delegating to sub-loaders. """

        out = {}
        for col in columns:
            try:
                loader = self._loaders.get(col)
                if loader is None:
                    loader = self._loaders[col.unspecialize()]
            except KeyError:
                raise ValueError("Couldn't find loader for %s" % col)
            out.update(
                loader.load_adjusted_array(domain, [col], dates, sids, mask)
            )
        return out