public static <V extends @Nullable Object> ListenableFuture<V> immediateCancelledFuture() {
    ListenableFuture<Object> instance = ImmediateCancelledFuture.INSTANCE;
    if (instance != null) {
      return (ListenableFuture<V>) instance;
    }
    return new ImmediateCancelledFuture<>();
  }

  /**

    Module System.
 *  New: Log gzipped bodies when `HttpLoggingInterceptor` is used as a network
    interceptor.
 *  New: `Protocol.QUIC` constant. This protocol is not supported but this
    constant is included for completeness.
 *  New: Upgrade to Okio 1.14.0.

     ```xml
     <dependency>
       <groupId>com.squareup.okio</groupId>
       <artifactId>okio</artifactId>

          <type>String</type>
        </field>
        <field>
          <name>properties</name>
          <version>3.0.0+</version>
          <description>Properties about the contributor, such as an instant messenger handle.</description>
          <type>Properties</type>
          <association xml.mapStyle="inline">
            <type>String</type>
            <multiplicity>*</multiplicity>
          </association>

under the License.
-->

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-install-plugin</artifactId>
  <version>0.1</version>
  <packaging>maven-plugin</packaging>

META-INF/MANIFEST.MF Manifest-Version: 1.0 Archiver-Version: Plexus Archiver Created-By: Apache Maven Built-By: BEBE Build-Jdk: 1.6.0_07 META-INF/maven/plugin.xml A test plugin to assist testing of Maven core. org.apache.maven.plugins maven-install-plugin 0.1 install false true install Does nothing. false true false false false true org.apache.maven.plugin.coreit.ItMojo java per-lookup once-per-session org.apache.maven maven-plugin-api jar 2.0 org/apache/maven/plugin/coreit/ItMojo.class package org.apache.maven.plugin.coreit;...

/// info | Informação

Para usar o `TestClient`, primeiro instale o <a href="https://www.python-httpx.org" class="external-link" target="_blank">`httpx`</a>.

Certifique-se de criar um [ambiente virtual](../virtual-environments.md){.internal-link target=_blank}, ativá-lo e instalá-lo, por exemplo:

```console
$ pip install httpx
```

///

Importe `TestClient`.

/// info | Informação

Para usar formulários, primeiro instale <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a>.

Certifique-se de criar um [ambiente virtual](../virtual-environments.md){.internal-link target=_blank}, ativá-lo e então instalá-lo, por exemplo:

```console
$ pip install python-multipart
```

///

## Importe `Form` { #import-form }

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>test</groupId>
    <artifactId>other</artifactId>
    <version>0.1-SNAPSHOT</version>

    <dependencyManagement>
        <dependencies>

## Eine Instanz erstellen { #create-an-instance }

Wir könnten eine Instanz dieser Klasse erstellen mit:

{* ../../docs_src/dependencies/tutorial011_an_py39.py hl[18] *}

Und auf diese Weise können wir unsere Abhängigkeit „parametrisieren“, die jetzt `"bar"` enthält, als das Attribut `checker.fixed_content`.

## Die Instanz als Abhängigkeit verwenden { #use-the-instance-as-a-dependency }

Möglicherweise stellen Sie fest, dass Sie zum Erstellen einer Instanz einer Python-Klasse die gleiche Syntax verwenden.

Zum Beispiel:

```Python
class Cat:
    def __init__(self, name: str):
        self.name = name


fluffy = Cat(name="Mr Fluffy")
```

In diesem Fall ist `fluffy` eine Instanz der Klasse `Cat`.

Und um `fluffy` zu erzeugen, rufen Sie `Cat` auf.