really needed (ASCII art, table, or long link)
+ If there is a corresponding issue, add either `Fixes #1234` or `Updates #1234`
  (the latter if this is not a complete fix) to this comment
+ If referring to a repo other than `golang/go` you can use the
  `owner/repo#issue_number` syntax: `Fixes golang/tools#1234`
+ We do not use Signed-off-by lines in Go. Please don't add them.
  Our Gerrit server & GitHub bots enforce CLA compliance instead.

        pushedHeaders.add(Header(Header.TARGET_AUTHORITY, url(pushPromise.path).host))
        pushedHeaders.add(Header(Header.TARGET_METHOD, pushPromise.method))
        pushedHeaders.add(Header(Header.TARGET_PATH, pushPromise.path))
        val pushPromiseHeaders = pushPromise.headers
        for ((name, value) in pushPromiseHeaders) {
          pushedHeaders.add(Header(name, value))
        }

         .add("publicobject.com",   "sha1/DmxUShsZuNiqPQsX2Oi9uv2sCnw=")
         .add("*.publicobject.com", "sha1/DmxUShsZuNiqPQsX2Oi9uv2sCnw=")
         .add("publicobject.com",   "sha1/SXxoaOSEzPC6BgGmxAt/EAcsajw=")
         .add("*.publicobject.com", "sha1/SXxoaOSEzPC6BgGmxAt/EAcsajw=")
         .add("publicobject.com",   "sha1/blhOM3W9V/bVQhsWAcLYwPU6n24=")

   * {@code ClassCastException} for any elements {@code e1} and {@code e2} in the multiset. If the
   * user attempts to add an element to the multiset that violates this constraint (for example, the
   * user attempts to add a string element to a set whose elements are integers), the {@code
   * add(Object)} call will throw a {@code ClassCastException}.
   *

    public boolean contains(Object object) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.contains(object);
    }

    @Override
    public boolean add(E element) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.add(element);
    }

    @Override
    public boolean containsAll(Collection<?> collection) {
      assertTrue(Thread.holdsLock(mutex));

///

## Add custom headers { #add-custom-headers }

There are some situations in where it's useful to be able to add custom headers to the HTTP error. For example, for some types of security.

You probably won't need to use it directly in your code.

But in case you needed it for an advanced scenario, you can add custom headers:

            projects.add(project);
            if (includeModules) {
                for (String module : project.getModules()) {
                    File modulePom = new File(pom.getParentFile(), module);
                    if (modulePom.isDirectory()) {
                        modulePom = new File(modulePom, "pom.xml");
                    }

			if opts.UndoWrite {
				p.storage.setWriteAttribute(p.totalWrites.Add(^uint64(0)))
				return
			}

			if fi.Deleted {
				// Delete markers are a write operation not a permanent delete.
				p.storage.setWriteAttribute(p.totalWrites.Add(1))
				return
			}

			p.storage.setDeleteAttribute(p.totalDeletes.Add(1))
		}
	}()

	w := xioutil.NewDeadlineWorker(globalDriveConfig.GetMaxTimeout())

        MavenOptions cliOptions = parseMavenCliOptions(context.parserRequest.args());
        result.add(cliOptions);
        // atFile option
        if (cliOptions.atFile().isPresent()) {
            Path file = context.cwd.resolve(cliOptions.atFile().orElseThrow());
            if (Files.isRegularFile(file)) {
                result.add(parseMavenAtFileOptions(file));
            } else {

### Add some custom `tags`, `responses`, and `dependencies` { #add-some-custom-tags-responses-and-dependencies }

We are not adding the prefix `/items` nor the `tags=["items"]` to each *path operation* because we added them to the `APIRouter`.