def METHOD_NAME():
    with pytest.raises(stix2.exceptions.InvalidValueError) as excinfo:
        stix2.v20.Relationship(type='xxx', **RELATIONSHIP_KWARGS)
    assert excinfo.value.cls == stix2.v20.Relationship
    assert excinfo.value.prop_name == "type"
    assert excinfo.value.reason == "must equal 'relationship'."
    assert str(excinfo.value) == "Invalid value for Relationship 'type': must equal 'relationship'."