def METHOD_NAME(token_client, organizer, customer, membership):
    resp = token_client.patch(
        '/api/v1/organizers/{}/memberships/{}/'.format(organizer.slug, membership.pk),
        format='json',
        data={
            "date_end": "2021-04-03T23:59:59.999999Z",
        }
    )
    assert resp.status_code == 200
    membership.refresh_from_db()
    assert membership.date_end.isoformat() == "2021-04-03T23:59:59.999999+00:00"
    with scopes_disabled():
        other_customer = organizer.customers.create()
    resp = token_client.patch(
        '/api/v1/organizers/{}/memberships/{}/'.format(organizer.slug, membership.pk),
        format='json',
        data={
            "customer": other_customer.identifier,
            "testmode": True,
        }
    )
    assert resp.status_code == 200
    membership.refresh_from_db()
    assert membership.customer == customer  # change is ignored
    assert not membership.testmode  # change is ignored