}

        /**
         * Deletes old documents from the search index.
         * This method removes documents that were indexed in previous
         * crawling sessions for the same data configuration, keeping
         * only the documents from the current session.
         *
         * <p>The deletion process:</p>
         * <ul>
         *   <li>Checks if old document deletion is enabled</li>

If you are building an application or a web API, it's rarely the case that you can put everything in a single file.

**FastAPI** provides a convenience tool to structure your application while keeping all the flexibility.

/// info

If you come from Flask, this would be the equivalent of Flask's Blueprints.

///

## An example file structure { #an-example-file-structure }

   * reconstructed using public factory methods. This ensures that the implementation types remain
   * as implementation details.
   *
   * <p>Since the bimap is immutable, ImmutableBiMap doesn't require special logic for keeping the
   * bimap and its inverse in sync during serialization, the way AbstractBiMap does.
   */
  @J2ktIncompatible // serialization
  private static final class SerializedForm<K, V> extends ImmutableMap.SerializedForm<K, V> {

{* ../../docs_src/behind_a_proxy/tutorial001_py39.py hl[6] *}

And the proxy would be **"stripping"** the **path prefix** on the fly before transmitting the request to the app server (probably Uvicorn via FastAPI CLI), keeping your application convinced that it is being served at `/app`, so that you don't have to update all your code to include the prefix `/api/v1`.

Up to here, everything would work as normally.

**OkHttp now supports Happy Eyeballs ([RFC 8305][rfc_8305]) for IPv4+IPv6 networks.** It attempts
both IPv6 and IPv4 connections concurrently, keeping whichever connects first.

**We’ve improved our Kotlin APIs.** You can skip the builder:

```kotlin
val request = Request(
  url = "https://cash.app/".toHttpUrl(),
)
```

  // The `table` array always has a size that is a power of 2. The hashcode of a key in the map
  // is masked in order to correspond to the current table size. For example, if the table size
  // is 128 then the mask is 127 == 0x7f, keeping the bottom 7 bits of the hash value.
  // If a key hashes to 0x89abcdef the mask reduces it to 0x89abcdef & 0x7f == 0x6f. We'll call this
  // the "short hash".
  //

        Set<Path> modifiedPoms = new HashSet<>();
        Set<Path> errorPoms = new HashSet<>();

        try {
            // Phase 1: Write all modifications to temp directory (keeping project structure)
            Path tempDir = createTempProjectStructure(context, pomMap);

            // Phase 2: For each POM, build effective model using the session and analyze plugins

```

</details>

## What is a Container { #what-is-a-container }

Containers (mainly Linux containers) are a very **lightweight** way to package applications including all their dependencies and necessary files while keeping them isolated from other containers (other applications or components) in the same system.

  // The `table` array always has a size that is a power of 2. The hashcode of a key in the map
  // is masked in order to correspond to the current table size. For example, if the table size
  // is 128 then the mask is 127 == 0x7f, keeping the bottom 7 bits of the hash value.
  // If a key hashes to 0x89abcdef the mask reduces it to 0x89abcdef & 0x7f == 0x6f. We'll call this
  // the "short hash".
  //

        do {
          int shift = min(remainingPowersOf2, Long.numberOfLeadingZeros(a));
          // shift is either the number of powers of 2 left to multiply a by, or the biggest shift
          // possible while keeping a in an unsigned long.
          a = UnsignedLongs.remainder(a << shift, m);
          remainingPowersOf2 -= shift;
        } while (remainingPowersOf2 > 0);
        return a;
      }

      @Override