n:            27,
			want:         26,
			wantErr:      io.EOF,
			wantBuffered: 0,
		},
		// Any error from filling shouldn't show up until we
		// get past the valid bytes. Here we return 5 valid bytes at the same time
		// as an error, but test that we don't see the error from Discard.
		{
			name: "fill error, discard less",
			r: newScriptedReader(func(p []byte) (n int, err error) {

			},
			{
				Name:     "bar.txt",
				Content:  []byte("bar\n"),
				Modified: time.Date(1979, 11, 30, 0, 0, 0, 0, time.UTC),
				Mode:     0666,
			},
		},
	},
	// Tests that we verify (and accept valid) crc32s on files
	// with crc32s in their file header (not in data descriptors)
	{
		Name: "crc32-not-streamed.zip",
		File: []ZipTestFile{
			{
				Name:     "foo.txt",
				Content:  []byte("foo\n"),

    app = FastAPI()
    with pytest.raises(FastAPIError) as e:

        @app.get("/")
        def read_root() -> Union[Response, None]:
            return Response(content="Foo")  # pragma: no cover

    assert "valid Pydantic field type" in e.value.args[0]
    assert "parameter response_model=None" in e.value.args[0]


def test_openapi_schema():
    response = client.get("/openapi.json")

		case guessHas:
			schema.guessRelation(relation, field, guessEmbeddedHas)
		// case guessEmbeddedHas:
		default:
			schema.err = fmt.Errorf("invalid field found for struct %v's field %s: define a valid foreign key for relations or implement the Valuer/Scanner interface",
				schema, field.Name)
		}
	}

	switch gl {
	case guessBelongs:
		primarySchema, foreignSchema = relation.FieldSchema, schema

the remainder of the terms of this Agreement, and without further
action by the parties hereto, such provision shall be reformed to the
minimum extent necessary to make such provision valid and enforceable.

If Recipient institutes patent litigation against any entity
(including a cross-claim or counterclaim in a lawsuit) alleging that the
Program itself (excluding combinations of the Program with other software

            assertTrue(hasExecPlugin, "Should include maven-exec-plugin upgrade");
        }

        @Test
        @DisplayName("should have valid plugin upgrade definitions")
        void shouldHaveValidPluginUpgradeDefinitions() throws Exception {
            List<PluginUpgrade> upgrades = PluginUpgradeStrategy.getPluginUpgrades();

		return nil, err
	}
	return etag, nil
}

// Parse parses s as an S3 ETag, returning the result.
// The string can be an encrypted, singlepart
// or multipart S3 ETag. It returns an error if s is
// not a valid textual representation of an ETag.
func Parse(s string) (ETag, error) {
	const strict = false
	return parse(s, strict)
}

// parse parse s as an S3 ETag, returning the result.
// It operates in one of two modes:

					"GNU.sparse.map": "0,0",  // Should be ignored
					"comment":        "Hello, 世界",
					"GOLANG.pkg":     "tar",
				},
			}, nil},
			testClose{nil},
		},
	}, {
		// Craft a theoretically valid PAX archive with global headers.
		// The GNU and BSD tar tools do not parse these the same way.
		//
		// BSD tar v3.1.2 parses and ignores all global headers;
		// the behavior is verified by researching the source code.

```

O parâmetro `name` **ainda é obrigatório** (não *opcional*) porque ele não possui um valor padrão. Mesmo assim, `name` aceita `None` como valor:

```Python
say_hi(name=None)  # This works, None is valid 🎉
```

A boa notícia é, quando você estiver no Python 3.10 você não precisará se preocupar mais com isso, pois você poderá simplesmente utilizar o `|` para definir uniões de tipos:

// This will make the branch rebalance itself when scanned if the distribution of objects has changed.

// scanDataFolder will scanner the basepath+cache.Info.Name and return an updated cache.
// The returned cache will always be valid, but may not be updated from the existing.
// Before each operation sleepDuration is called which can be used to temporarily halt the scanner.
// If the supplied context is canceled the function will return at the first chance.