* predicate. The returned multimap is a live view of {@code unfiltered}; changes to one affect
   * the other.
   *
   * <p>The resulting multimap's views have iterators that don't support {@code remove()}, but all
   * other methods are supported by the multimap and its views. When adding a key that doesn't
   * satisfy the predicate, the multimap's {@code put()}, {@code putAll()}, and {@code

* and from it, import the function `get_token_header`.

That would refer to some package above `app/`, with its own file `__init__.py`, etc. But we don't have that. So, that would throw an error in our example. 🚨

But now you know how it works, so you can use relative imports in your own apps no matter how complex they are. 🤓

    return {"Hello": "World"}


@app.get("/items/{item_id}")
async def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

**Note**:

If you don't know, check the _"In a hurry?"_ section about <a href="https://fastapi.tiangolo.com/async/#in-a-hurry" target="_blank">`async` and `await` in the docs</a>.

</details>

### Run it { #run-it }

Run the server with:

## Épinglez votre version de `fastapi`

Tout d'abord il faut "épingler" la version de **FastAPI** que vous utilisez à la dernière version dont vous savez
qu'elle fonctionne correctement pour votre application.

Par exemple, disons que vous utilisez la version `0.45.0` dans votre application.

        assertTrue(result.contains("secretkey={cipher}"));
        assertFalse(result.contains("secretkey=unencrypted"));

        // Test with keys that don't match pattern
        value = "normalfield=value\npassword=secret";
        result = ParameterUtil.encrypt(value);

              <exclude>%regex[.*PackageSanityTests.*.class]</exclude>
              <!-- FeatureUtilTest.*ExampleDerivedInterfaceTester, com.google.common.io.*Tester, incidentally FeatureSpecificTestSuiteBuilderTest.MyAbstractTester (but we don't care either way because it's not meant to run on its own but works OK if it does)... but not NullPointerTesterTest, etc. -->
              <exclude>%regex[.*Tester.class]</exclude>

              assertThat(bloomFilter.mightContain(key)).isTrue();

              // If this check ever fails, that means we need to either bump the
              // number of expected insertions or don't run the test for so long.
              // Don't forget, the bloom filter slowly saturates over time and the
              // expected false positive probability goes up!

              <exclude>%regex[.*PackageSanityTests.*.class]</exclude>
              <!-- FeatureUtilTest.*ExampleDerivedInterfaceTester, com.google.common.io.*Tester, incidentally FeatureSpecificTestSuiteBuilderTest.MyAbstractTester (but we don't care either way because it's not meant to run on its own but works OK if it does)... but not NullPointerTesterTest, etc. -->
              <exclude>%regex[.*Tester.class]</exclude>

    assertEquals((Integer) 5, converter.convert("5"));
    assertEquals("5", converter.reverse().convert(5));
  }

  // Null-passthrough violates our nullness annotations, so we don't support it under J2KT.
  @J2ktIncompatible
  public void testNullIsPassedThrough() {
    Converter<String, String> nullsArePassed = sillyConverter(false);
    assertEquals("forward", nullsArePassed.convert("foo"));

    }

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

    @Override
    public Iterator<E> iterator() {
      // We explicitly don't lock for iterator()
      assertFalse(Thread.holdsLock(mutex));
      return delegate.iterator();
    }

    @Override
    public int size() {
      assertTrue(Thread.holdsLock(mutex));