# Virtual Environments { #virtual-environments }

When you work in Python projects you probably should use a **virtual environment** (or a similar mechanism) to isolate the packages you install for each project.

/// info

If you already know about virtual environments, how to create them and use them, you might want to skip this section. 🤓

///

/// tip

A **virtual environment** is different than an **environment variable**.

  //   timeout is small we shouldn't park(). This needs to be traded off with the cpu overhead of
  //   spinning, so we use SPIN_THRESHOLD_NANOS which is what AbstractQueuedSynchronizer uses for
  //   similar purposes.
  // * We want to behave reasonably for timeouts of 0
  // * We are more responsive to completion than timeouts. This is because parkNanos depends on

import okio.BufferedSink
import okio.BufferedSource
import okio.buffer
import okio.sink
import okio.source
import okio.use

/**
 * A limited implementation of SOCKS Protocol Version 5, intended to be similar to MockWebServer.
 * See [RFC 1928](https://www.ietf.org/rfc/rfc1928.txt).
 */
class SocksProxy {
  private val executor = Executors.newCachedThreadPool(threadFactory("SocksProxy"))

 *
 * <pre>
 *
 * InetAddress addr = NbtAddress.getByName("jmorris2").getInetAddress();
 * </pre>
 *
 *  * From a UNIX platform with Samba installed you can perform similar
 * diagnostics using the <code>nmblookup</code> utility.
 *
 * @author Michael B. Allen
 * @see java.net.InetAddress
 * @since jcifs-0.1
 */
public interface NetbiosAddress extends Address {

    /**

└── static/
```

### Download the files { #download-the-files }

Download the static files needed for the docs and put them on that `static/` directory.

You can probably right-click each link and select an option similar to `Save link as...`.

**Swagger UI** uses the files:

* <a href="https://cdn.jsdelivr.net/npm/swagger-ui-dist@5/swagger-ui-bundle.js" class="external-link" target="_blank">`swagger-ui-bundle.js`</a>

            throw new IOException("Connection not established");
        }

        try {
            // In real implementation, this would perform RDMA write:
            // Similar to rdmaRead but with IBV_WR_RDMA_WRITE opcode

            log.debug("DiSNI RDMA write completed, {} bytes", length);

        } catch (Exception e) {
            state = RdmaConnectionState.ERROR;

    @Nonnull
    Optional<Boolean> ignoreTransitiveRepositories();

    /**
     * Specifies "@file"-like file, to load up command line from. It may contain goals as well. Format is one parameter
     * per line (similar to {@code maven.conf}) and {@code '#'} (hash) marked comment lines are allowed. Goals, if
     * present, are appended, to those specified on CLI input, if any.
     */
    Optional<String> atFile();

    /**

    assert input.length >= offset + 8;
    // Delegates to the fast (unsafe) version or the fallback.
    return byteArray.getLongLittleEndian(input, offset);
  }

  /**
   * Similar to load64, but allows offset + 8 > input.length, padding the result with zeroes. This
   * has to explicitly reverse the order of the bytes as it packs them into the result which makes
   * it slower than the native version.
   *

### Use o sub-modelo como um tipo

E então podemos usa-lo como o tipo de um atributo:

{* ../../docs_src/body_nested_models/tutorial004.py hl[20] *}

Isso significa que o **FastAPI** vai esperar um corpo similar à:

```JSON
{
    "name": "Foo",
    "description": "The pretender",
    "price": 42.0,
    "tax": 3.2,
    "tags": ["rock", "metal", "bar"],
    "image": {
        "url": "http://example.com/baz.jpg",

  // final fields.
  //
  // For simplicity the rest of this description will discuss Futures.catching since it is the
  // simplest instance, though very similar descriptions apply to many other classes in this file.
  //
  // In the constructor of AbstractCatchingFuture, the delegate future is assigned to a field