*/
    if (throwable instanceof Error) {
      /*
       * TODO(cpovirk): Do we really want to log this if we called setException(throwable) and it
       * returned true? This was intentional (CL 46470009), but it seems odd compared to how we
       * normally handle Error.
       *
       * Similarly, do we really want to log the same Error more than once?
       */
      log(throwable);
    }
  }

///

Here we define the config `env_file` inside of your Pydantic `Settings` class, and set the value to the filename with the dotenv file we want to use.

### Creating the `Settings` only once with `lru_cache`

Reading a file from disk is normally a costly (slow) operation, so you probably want to do it only once and then reuse the same settings object, instead of reading it for each request.

But every time we do:

```Python

    params {
        text(
            "performance.baselines",
            "",
            display = ParameterDisplay.PROMPT,
            allowEmpty = true,
            description = "The baselines you want to run performance tests against. Empty means default baseline."
        )
        text(
            "testProject",
            "",
            display = ParameterDisplay.PROMPT,
            allowEmpty = false,

      // the result will definitely fit into a long
      long result = 1;
      for (int i = n1 + 1; i <= n2; i++) {
        result *= i;
      }
      return BigInteger.valueOf(result);
    }

    /*
     * We want each multiplication to have both sides with approximately the same number of digits.
     * Currently, we just divide the range in half.
     */
    int mid = (n1 + n2) >>> 1;

    private RepositorySystem repoSystem;

    @Inject
    private LegacySupport legacySupport;

    private Map<Object, MergeableMetadata> relatedMetadata = new ConcurrentHashMap<>();

    /**
     * @deprecated we want to use the artifact method only, and ensure artifact.file is set
     *             correctly.
     */
    @Deprecated
    public void deploy(
            String basedir,
            String finalName,

    for (Field field : cls.getDeclaredFields()) {
      /*
       * Coverage mode generates synthetic fields.  If we ever add private
       * fields, they will cause similar problems, and we may want to switch
       * this check to isAccessible().
       */
      if (!field.isSynthetic() && field.getType() == String.class) {
        builder.add(field);
      }
    }
    return builder.build();
  }

    for (Field field : cls.getDeclaredFields()) {
      /*
       * Coverage mode generates synthetic fields.  If we ever add private
       * fields, they will cause similar problems, and we may want to switch
       * this check to isAccessible().
       */
      if (!field.isSynthetic() && field.getType() == String.class) {
        builder.add(field);
      }
    }
    return builder.build();
  }

     * least old versions), so we mostly do. This is useful because we don't actually run our CI on
     * Windows under Java 8, at least as of this writing.
     *
     * Under Windows in particular, we want to test that:
     *
     * - Under Java 9+, createTempDir() succeeds because it can look up the *real* username, rather
     * than relying on the one from the system property.
     *

Now, let's see how you could use that to return a custom response.

Let's say that you want to return an <a href="https://en.wikipedia.org/wiki/XML" class="external-link" target="_blank">XML</a> response.

You could put your XML content in a string, put that in a `Response`, and return it:

```Python hl_lines="1  18"

Keep in mind that custom proprietary headers can be added <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">using the 'X-' prefix</a>.