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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_vnic_template_for_vlan(self, vlan_id):
 """Deletes VNIC Template for a vlan_id and physnet if it exists."""

        with self.session.begin(subtransactions=True):
            try:
                self.session.query(ucsm_model.VnicTemplate).filter_by(
                    vlan_id=vlan_id).delete()
            except orm.exc.NoResultFound:
                return