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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 delete(self, using=None):
 """ If the organization user is also the owner, this should not be deleted unless it's part of a cascade from the Organization. If there is no owner then the deletion should proceed. """

        from organizations.exceptions import OwnershipRequired

        try:
            if self.organization.owner.organization_user.pk == self.pk:
                raise OwnershipRequired(
                    _(
                        "Cannot delete organization owner "
                        "before organization or transferring ownership."
                    )
                )
        # TODO This line presumes that OrgOwner model can't be modified
        except self._org_owner_model.DoesNotExist:
            pass
        super(AbstractBaseOrganizationUser, self).delete(using=using)