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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 end_index(self):
 """Return the 1-based index of the last item on this page."""

        paginator = self.paginator
        # Special case for the last page because there can be orphans.
        if self.number == paginator.num_pages:
            return paginator.count
        return (self.number - 1) * paginator.per_page + paginator.first_page