*  @author Victor Jonsson, http://victorjonsson.se
 *  @license MIT
 */

### Step 4: define the **path operation function**

This is our "**path operation function**":

* **path**: is `/`.
* **operation**: is `get`.
* **function**: is the function below the "decorator" (below `@app.get("/")`).

```Python hl_lines="7"
{!../../../docs_src/first_steps/tutorial001.py!}
```

This is a Python function.

}

// BenchmarkSelectAll_100K - benchmark * function with 100k records.
func BenchmarkSelectAll_100K(b *testing.B) {
	benchmarkSelectAll(b, 100*humanize.KiByte)
}

// BenchmarkSelectAll_1M - benchmark * function with 1m records.
func BenchmarkSelectAll_1M(b *testing.B) {
	benchmarkSelectAll(b, 1*humanize.MiByte)
}

// BenchmarkSelectAll_2M - benchmark * function with 2m records.

 *  @author Victor Jonsson, http://victorjonsson.se
 *  @license MIT
 */

 *  @author Victor Jonsson, http://victorjonsson.se
 *  @license MIT
 */

public class MapComputeIfPresentTester<K, V> extends AbstractMapTester<K, V> {

  @MapFeature.Require(SUPPORTS_PUT)
  public void testComputeIfPresent_supportedAbsent() {
    assertNull(
        "computeIfPresent(notPresent, function) should return null",
        getMap()
            .computeIfPresent(
                k3(),
                (k, v) -> {
                  throw new AssertionFailedError();
                }));
    expectUnchanged();

 *  @author Victor Jonsson, http://victorjonsson.se
 *  @license MIT
 */

 *  @author Victor Jonsson, http://victorjonsson.se
 *  @license MIT
 */

 *  @author Victor Jonsson, http://victorjonsson.se
 *  @license MIT
 */

      }
    }
  }

  /**
   * Returns a function that delegates to the {@link Interner#intern} method of the given interner.
   *
   * @since 8.0
   */
  public static <E> Function<E, E> asFunction(Interner<E> interner) {
    return new InternerFunction<>(checkNotNull(interner));
  }

  private static class InternerFunction<E> implements Function<E, E> {

    private final Interner<E> interner;