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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 _first(self, **spec):
 """ Get the earliest entry in this category, optionally including subcategories """

        for record in self._entries(spec).order_by(model.Entry.local_date,
                                                   model.Entry.id)[:1]:
            return entry.Entry(record)
        return None