'Test __init__ when only one field is set.'

def test_init_defaults(self):

    all_defaults = {field: self._req_default(field) for field in self.all_fields}
    for field in self.fields:
        fields = {field: self.fields[field]}
        req = objects.CleanupRequest(mock.sentinel.context, **fields)
        expected = all_defaults.copy()
        expected.update(fields)
        self.assertDictEqual(expected, self._req_as_dict(req))
