// Use it with other programs, like
$ echo "Hello $Env:MY_NAME"

Hello Wade Wilson
```

</div>

////

## Read env vars in Python { #read-env-vars-in-python }

You could also create environment variables **outside** of Python, in the terminal (or with any other method), and then **read them in Python**.

For example you could have a file `main.py` with:

```Python hl_lines="3"
import os

    ByteSource source = out.asByteSource();

    out.write(data);
    assertThat(source.read()).isEqualTo(data);

    out.reset();
    assertThat(source.read()).isEmpty();

    out.write(data);
    assertThat(source.read()).isEqualTo(data);

    out.close();
  }

  private static boolean isAndroid() {

    ByteSource source = out.asByteSource();

    out.write(data);
    assertThat(source.read()).isEqualTo(data);

    out.reset();
    assertThat(source.read()).isEmpty();

    out.write(data);
    assertThat(source.read()).isEqualTo(data);

    out.close();
  }

  private static boolean isAndroid() {

    assertTrue(source.wasStreamOpened());
    assertFalse(source.wasStreamClosed());

    StringWriter writer = new StringWriter();
    char[] buf = new char[64];
    int read;
    while ((read = reader.read(buf)) != -1) {
      writer.write(buf, 0, read);
    }
    reader.close();
    writer.close();

    assertTrue(source.wasStreamClosed());
    assertEquals(STRING, writer.toString());
  }

		Method: Deflate,
		Mode:   0755 | fs.ModeDevice | fs.ModeCharDevice,
	},
}

func TestWriter(t *testing.T) {
	largeData := make([]byte, 1<<17)
	if _, err := rand.Read(largeData); err != nil {
		t.Fatal("rand.Read failed:", err)
	}
	writeTests[1].Data = largeData
	defer func() {
		writeTests[1].Data = nil
	}()

	// write a zip file
	buf := new(bytes.Buffer)
	w := NewWriter(buf)

		panic("Failed to acquire read lock")
	}
	// fmt.Println("1st read lock acquired, waiting...")

	if !lrwm.GetRLock(ctx, "", "object1", time.Second) {
		panic("Failed to acquire read lock")
	}
	// fmt.Println("2nd read lock acquired, waiting...")

	go func() {
		time.Sleep(2 * time.Second)
		lrwm.RUnlock()
		// fmt.Println("1st read lock released, waiting...")
	}()

	go func() {

    }

    @Override
    public Model read(File input, Map<String, ?> options) throws IOException {
        return reader.read(input, options);
    }

    @Override
    public Model read(Reader input, Map<String, ?> options) throws IOException {
        return reader.read(input, options);
    }

    @Override
    public Model read(InputStream input, Map<String, ?> options) throws IOException {

     */
    String defaultValue() default "";

    /**
     * Specifies whether the configuration property is read-only.
     *
     * @return true if the property is read-only, false otherwise
     */
    boolean readOnly() default false;

    /**
     * Property source, which determines when and where the property will be read from or set for consumption.

) {
  private val countingSource: CountingSource = CountingSource(source)
  private val source: BufferedSource = countingSource.buffer()

  /** Total bytes read thus far. */
  private val byteCount: Long
    get() = countingSource.bytesRead - source.buffer.size

  /** How many bytes to read before [peekHeader] should return false, or -1L for no limit. */
  private var limit = -1L

	}

	d.decrypter = decrypter
	return nil
}

func (d *DecryptBlocksReader) Read(p []byte) (int, error) {
	var err error
	var n1 int
	decPartSize, _ := sio.DecryptedSize(uint64(d.parts[d.partIndex].Size))
	unreadPartLen := int64(decPartSize) - d.partDecRelOffset
	if int64(len(p)) < unreadPartLen {
		n1, err = d.decrypter.Read(p)
		if err != nil {
			return 0, err
		}
		d.partDecRelOffset += int64(n1)