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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 _get_entities(self, user, ids):
 """Return entities queryset based on provided entity ids."""

        queryset = get_objects_for_user(user, 'view_entity', Entity.objects.filter(id__in=ids))
        actual_ids = queryset.values_list('id', flat=True)
        missing_ids = list(set(ids) - set(actual_ids))
        if missing_ids:
            raise exceptions.ParseError(
                "Entities with the following ids not found: {}" .format(', '.join(map(str, missing_ids)))
            )

        return queryset