</li>

<li>
In all other cases, <code>x.f</code> is illegal.
</li>

<li>
If <code>x</code> is of pointer type and has the value
<code>nil</code> and <code>x.f</code> denotes a struct field,
assigning to or evaluating <code>x.f</code>
causes a <a href="#Run_time_panics">run-time panic</a>.
</li>

<li>
If <code>x</code> is of interface type and has the value
<code>nil</code>, <a href="#Calls">calling</a> or

     */
    abstract <K, V> ReferenceEntry<K, V> newEntry(
        Segment<K, V> segment, K key, int hash, @CheckForNull ReferenceEntry<K, V> next);

    /**
     * Copies an entry, assigning it a new {@code next} entry.
     *
     * @param original the entry to copy. But avoid calling {@code getKey} on it: Instead, use the

</li>

<li>
In all other cases, <code>x.f</code> is illegal.
</li>

<li>
If <code>x</code> is of pointer type and has the value
<code>nil</code> and <code>x.f</code> denotes a struct field,
assigning to or evaluating <code>x.f</code>
causes a <a href="#Run_time_panics">run-time panic</a>.
</li>

<li>
If <code>x</code> is of interface type and has the value
<code>nil</code>, <a href="#Calls">calling</a> or

	"github.com/dustin/go-humanize"
	jwtgo "github.com/golang-jwt/jwt/v4"
	jsoniter "github.com/json-iterator/go"
)

// SigningMethodHMAC - Implements the HMAC-SHA family of signing methods signing methods
// Expects key type of []byte for both signing and validation
type SigningMethodHMAC struct {
	Name       string
	Hash       crypto.Hash
	HasherPool sync.Pool
}

// Specific instances for HS256, HS384, HS512
var (

Tout d'abord, sachez que vous pouvez mélanger les déclarations des paramètres `Path`, `Query` et body, **FastAPI** saura quoi faire.

Vous pouvez également déclarer des paramètres body comme étant optionnels, en leur assignant une valeur par défaut à `None` :

//// tab | Python 3.10+

```Python hl_lines="18-20"
{!> ../../docs_src/body_multiple_params/tutorial001_an_py310.py!}
```

////

//// tab | Python 3.9+

## `python-jose` installieren.

Wir müssen <abbr title="JOSE: JavaScript Object Signing and Encryption">`python-jose`</abbr> installieren, um die JWT-Tokens in Python zu generieren und zu verifizieren:

<div class="termy">

```console
$ pip install "python-jose[cryptography]"

---> 100%
```

type SignatureDoesNotMatch struct{}

func (e SignatureDoesNotMatch) Error() string {
	return "The request signature we calculated does not match the signature you provided. Check your key and signing method."
}

// StorageFull storage ran out of space.
type StorageFull struct{}

func (e StorageFull) Error() string {
	return "Storage reached its minimum free drive threshold."
}

		}

		// Retrieve the credential's claims.
		secret, err := getTokenSigningKey()
		if err != nil {
			c.Fatalf("Error getting token signing key: %v", err)
		}
		claims, err := getClaimsFromTokenWithSecret(value.SessionToken, secret)
		if err != nil {
			c.Fatalf("Error getting claims from token: %v", err)
		}

		// Validate claims.

const iso8601TimeFormat = "2006-01-02T15:04:05.000Z"

// Excerpts from @lsegal - https://github.com/aws/aws-sdk-js/issues/659#issuecomment-120477258
//
//	User-Agent:
//
//	    This is ignored from signing because signing this causes problems with generating pre-signed URLs
//	    (that are executed by other agents) or when customers pass requests through proxies, which may
//	    modify the user-agent.
//
//	Authorization:
//

	},
	ErrSignatureDoesNotMatch: {
		Code:           "SignatureDoesNotMatch",
		Description:    "The request signature we calculated does not match the signature you provided. Check your key and signing method.",
		HTTPStatusCode: http.StatusForbidden,
	},
	ErrMethodNotAllowed: {
		Code:           "MethodNotAllowed",
		Description:    "The specified method is not allowed against this resource.",