Ein **Kontextmanager** in Python ist etwas, das Sie in einer `with`-Anweisung verwenden können, zum Beispiel kann `open()` als Kontextmanager verwendet werden:

```Python
with open("file.txt") as file:
    file.read()
```

In neueren Versionen von Python gibt es auch einen **asynchronen Kontextmanager**. Sie würden ihn mit `async with` verwenden:

```Python
async with lifespan(app):
    await do_stuff()
```

$ $Env:MY_NAME = "Wade Wilson"

// Verwenden Sie sie mit anderen Programmen, etwa
$ echo "Hello $Env:MY_NAME"

Hello Wade Wilson
```

</div>

////

## Umgebungsvariablen in Python lesen { #read-env-vars-in-python }

Sie können auch Umgebungsvariablen **außerhalb** von Python erstellen, im Terminal (oder mit jeder anderen Methode) und sie dann **in Python** lesen.

Zum Beispiel könnten Sie eine Datei `main.py` haben mit:

		for j := 0; j < loopCount; j++ {
			var tmp User
			err := tx.Session(&gorm.Session{}).First(&tmp, id).Error
			if err == nil || isUsingClosedConnError(err) {
				continue
			}
			t.Errorf("failed to read user of id %d due to %s, there should not be error", id, err)
			unexpectedError = true
			break
		}
	}(user.ID)

	wg.Add(1)
	go func() {
		defer wg.Done()
		<-writerFinish
		pdb.Close()
	}()

actions: # - "s3:CreateBucket" # - "s3:DeleteBucket" # - "s3:GetBucketLocation" # - "s3:ListBucket" # - "s3:ListBucketMultipartU" ## readonlyexamplepolic policy grants access to buckets with name starting with example. ## In addition, grants objects read permissions on buckets starting with example. # - name: readonlyexamplepolic # statements: # - resources: # - 'arn:aws:s3:::example*/*' # actions: # - "s3:GetObject" # - resources: # - 'arn:aws:s3:::example*' # actions: # - "s3:GetBucketLocation" #...

$ $Env:MY_NAME = "Wade Wilson"

// Usá-la com outros programas, como
$ echo "Hello $Env:MY_NAME"

Hello Wade Wilson
```

</div>

////

## Ler Variáveis de Ambiente no Python { #read-env-vars-in-python }

Você também pode criar variáveis de ambiente **fora** do Python, no terminal (ou com qualquer outro método) e depois **lê-las no Python**.

Por exemplo, você poderia ter um arquivo `main.py` com:

Use the following command to generate a private key with ECDSA:

```sh
openssl ecparam -genkey -name prime256v1 | openssl ec -out private.key
```

A response similar to this one should be displayed:

```
read EC key
writing EC key
```

Alternatively, use the following command to generate a private ECDSA key protected by a password:

```sh

run the below commands: 1. export POD_NAME=$(kubectl get pods --namespace {{ .Release.Namespace }} -l "release={{ .Release.Name }}" -o jsonpath="{.items[0].metadata.name}") 2. kubectl port-forward $POD_NAME 9000 --namespace {{ .Release.Namespace }} Read more about port forwarding here: http://kubernetes.io/docs/user-guide/kubectl/kubectl_port-forward/ You can now access Minio server on http://localhost:9000. Follow the below steps to connect to Minio server with mc client: 1. Download the Minio mc...

        try {
            final InputStream is = request.getInputStream();
            try {
                final byte[] buf = new byte[1024];
                while ((is.read(buf)) != -1) {}
            } catch (final Exception ignored) {} finally {
                try {
                    is.close();
                } catch (final Exception ignored) {}
            }

    accessed by another process" error. The <code>FILE_SHARE_READ</code>,
    <code>FILE_SHARE_WRITE</code>, and <code>FILE_SHARE_DELETE</code> may be
    combined with the bitwise OR '|' to specify that other peocesses may read,
    write, and/or delete the file while the jCIFS user has the file open.
     *
     * @param url An smb URL representing the file to write to

And when using `Depends(scope="request")` (the default), the exit code after `yield` is executed after the response is sent.

You can read more about it in the docs for [Dependencies with `yield` - Early exit and `scope`](../tutorial/dependencies/dependencies-with-yield.md#early-exit-and-scope).