def METHOD_NAME():
    person = Person(name='Timmy')
    org = Organization(name='ACME')
    person.member_of.add(Membership(org, person, id='acme-1'))
    db.session.add(person)
    db.session.flush()
    person2 = Person(name='Tommy')
    person2.member_of.add(Membership(org, person2, id='acme-1'))
    db.session.add(person2)
    with pytest.raises(DBError) as e:
        db.session.flush()
    assert 'One member id per organization' in str(e)