// The env var no longer exists afterwards
$ python main.py

Hello World from Python
```

</div>

!!! tip
    You can read more about it at <a href="https://12factor.net/config" class="external-link" target="_blank">The Twelve-Factor App: Config</a>.

### Types and validation

  private val routePlanner = FakeRoutePlanner()
  private val factory = routePlanner.factory
  private val taskFaker = routePlanner.taskFaker
  private val peer = MockHttp2Peer()

  /** The fake task runner prevents the cleanup runnable from being started.  */
  private val addressA = factory.newAddress("a")
  private val routeA1 = factory.newRoute(addressA)
  private val addressB = factory.newAddress("b")

import okhttp3.internal.connection.RoutePlanner
import okhttp3.internal.connection.RoutePlanner.ConnectResult

class FakeRoutePlanner(
  val factory: TestValueFactory = TestValueFactory(),
  val taskFaker: TaskFaker = factory.taskFaker,
) : RoutePlanner, Closeable {
  val pool = factory.newConnectionPool(routePlanner = this)
  val events = LinkedBlockingDeque<String>()
  var canceled = false
  var autoGeneratePlans = false

`tf.reverse_v2()` will remain until 1.0 final. * `tf.mul`, `tf.sub` and `tf.neg`
are deprecated in favor of `tf.multiply`, `tf.subtract` and `tf.negative`. *
`tf.pack` and `tf.unpack` are deprecated in favor of `tf.stack` and
`tf.unstack`. * `TensorArray.pack` and `TensorArray.unpack` are getting
deprecated in favor of `TensorArray.stack` and `TensorArray.unstack`. * The

 * provides symbol names from binary libraries in Standalone mode, which the Standalone declaration provider does not contain (to avoid
 * stub-indexing binary libraries). And in general, querying the symbol names provider might be faster since its sets are cached, which is
 * not necessarily the case for declaration providers (e.g. the IDE declaration provider hitting the index without caching).
 *

    ) = diagnostics.firstOrNull { diagnostic ->
        if (diagnostic.severity != Severity.ERROR) return@firstOrNull false
        if (diagnostic.factory in syntaxErrors) return@firstOrNull true
        val isResolutionError = diagnostic.factory in resolutionFailureErrors
        val isCallArgError = diagnostic.factory in callArgErrors
        val reportedPsi = diagnostic.psiElement
        val reportedPsiParent = reportedPsi.parent
        when {

* ✅ Refactor 2 tests, for consistency and simplification. PR [#9504](https://github.com/tiangolo/fastapi/pull/9504) by [@tiangolo](https://github.com/tiangolo).
* ✅ Refactor OpenAPI tests, prepare for Pydantic v2. PR [#9503](https://github.com/tiangolo/fastapi/pull/9503) by [@tiangolo](https://github.com/tiangolo).

 */
internal class FastFallbackExchangeFinderTest {
  private val taskFaker = TaskFaker()
  private val taskRunner = taskFaker.taskRunner

  /**
   * Note that we don't use the same [TaskFaker] for this factory. That way off-topic tasks like
   * connection pool maintenance tasks don't add noise to route planning tests.
   */
  private val routePlanner = FakeRoutePlanner(taskFaker = taskFaker)