User-Agent: OkHttp Example
Host: www.publicobject.com
Connection: Keep-Alive
Accept-Encoding: gzip

INFO: Received response for http://www.publicobject.com/helloworld.txt in 115.6ms
Server: nginx/1.4.6 (Ubuntu)
Content-Type: text/html
Content-Length: 193
Connection: keep-alive
Location: https://publicobject.com/helloworld.txt

	newSignature := getSignature(signingKey, stringToSign)

	return newSignature
}

// calculateSeedSignature - Calculate seed signature in accordance with
//   - http://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-streaming.html
//
// returns signature, error otherwise if the signature mismatches or any other
// error while parsing and validating.

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// dica

O segundo parâmetro em <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> é o valor padrão para o retorno.

Se nenhum valor for informado, `None` é utilizado por padrão, aqui definimos `"World"` como o valor padrão a ser utilizado.

///

constraints.ParametersScriptAssert.message  = script expression "{script}" didn't evaluate to true.
constraints.Range.message                   = {item} must be between {min} and {max}.
constraints.SafeHtml.message                = {item} may have unsafe html content.
constraints.ScriptAssert.message            = script expression "{script}" didn't evaluate to true.
constraints.URL.message                     = {item} must be a valid URL.

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip

Второй аргумент <a href=«https://docs.python.org/3.8/library/os.html#os.getenv» class=«external-link» target=«_blank»>`os.getenv()`</a> - это возвращаемое по умолчанию значение.

/// info

Tüm öğreticiyi zaten okuduysanız ve türler hakkında daha fazla bilgi için geri döndüyseniz, iyi bir kaynak:<a href="https://mypy.readthedocs.io/en/latest/cheat_sheet_py3.html" class="external-link" target="_blank"> the "cheat sheet" from `mypy`</a>.

labels.facet_contentLength_100kto500k=100kb - 500kb
labels.facet_contentLength_500kto1m=500kb - 1mb
labels.facet_contentLength_1m=1mb -  
labels.facet_filetype_title=Тип файла
labels.facet_filetype_html=HTML
labels.facet_filetype_word=MS Word
labels.facet_filetype_excel=MS Excel
labels.facet_filetype_powerpoint=MS PowerPoint
labels.facet_filetype_odt=ODF Word
labels.facet_filetype_ods=ODF Spreadsheet

constraints.Range.message                   = {item} muss zwischen {min} und {max} liegen.
constraints.SafeHtml.message                = {item} darf unsicheres HTML enthalten.
constraints.ScriptAssert.message            = Der Skript-Ausdruck "{script}" hat kein wahres Ergebnis geliefert.
constraints.URL.message                     = {item} muss eine gültige URL sein.

```

////

## `Union` 或者 `anyOf`

响应可以声明为两种类型的 `Union` 类型，即该响应可以是两种类型中的任意类型。

在 OpenAPI 中可以使用 `anyOf` 定义。

为此，请使用 Python 标准类型提示 <a href="https://docs.python.org/3/library/typing.html#typing.Union" class="external-link" target="_blank">`typing.Union`</a>：

/// note | "笔记"

  CYGWIN*) cygwin=true ;;
  MINGW*) mingw=true;;
  Darwin*) darwin=true
    # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
    # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
    if [ -z "$JAVA_HOME" ]; then
      if [ -x "/usr/libexec/java_home" ]; then
        export JAVA_HOME="`/usr/libexec/java_home`"
      else
        export JAVA_HOME="/Library/Java/Home"
      fi
    fi
    ;;