}

		if primaryKeyField == nil {
			schema.err = fmt.Errorf("invalid polymorphic type %v for %v on field %s, missing primaryKey field",
				relation.FieldSchema, schema, field.Name)
			return
		}

		// use same data type for foreign keys
		if copyableDataType(primaryKeyField.DataType) {
			relation.Polymorphic.PolymorphicID.DataType = primaryKeyField.DataType
		}

    assertNull(Callables.returning(null).call());

    Object value = new Object();
    Callable<Object> callable = Callables.returning(value);
    assertSame(value, callable.call());
    // Expect the same value on subsequent calls
    assertSame(value, callable.call());
  }

  @J2ktIncompatible
  @GwtIncompatible
  public void testAsAsyncCallable() throws Exception {
    String expected = "MyCallableString";

 *       String}.
 *   <li>{@code getElement} on a {@code Multiset.Entry<@Nullable String>} returns {@code @Nullable
 *       String}.
 * </ul>
 *
 * This is the same behavior as type-variable usages have to Kotlin and to the Checker Framework.
 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class ListEqualsTester<E> extends AbstractListTester<E> {
  public void testEquals_otherListWithSameElements() {
    assertTrue(
        "A List should equal any other List containing the same elements.",
        getList().equals(new ArrayList<E>(getOrderedElements())));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  public void testEquals_otherListWithDifferentElements() {

 *       String}.
 *   <li>{@code getElement} on a {@code Multiset.Entry<@Nullable String>} returns {@code @Nullable
 *       String}.
 * </ul>
 *
 * This is the same behavior as type-variable usages have to Kotlin and to the Checker Framework.
 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},

                                    // If we don't clean that up there might be leftover json files from other report builds running on the same machine.
                                    """
                                    results/performance/build/test-results-*.zip!performance-tests/report/css/*.css => $performanceResultsDir/

      }

    return dateFormat.format(date)
  }

  /**
   * A timestamp like "191216030210Z" or "20191215190210-0800" for 2019-12-15T19:02:10-08:00. This
   * is the same as [UTC_TIME] with the exception of the 4-digit year.
   */
  val GENERALIZED_TIME =
    BasicDerAdapter(
      name = "GENERALIZED TIME",
      tagClass = DerHeader.TAG_CLASS_UNIVERSAL,
      tag = 24L,

    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}
```

**Nota**:

Se você não sabe, verifique a seção _"Com pressa?"_ sobre <a href="https://fastapi.tiangolo.com/pt/async/#com-pressa" target="_blank">`async` e `await` nas docs</a>.

</details>

### Rode

Rode o servidor com:

 *       String}.
 *   <li>{@code getElement} on a {@code Multiset.Entry<@Nullable String>} returns {@code @Nullable
 *       String}.
 * </ul>
 *
 * This is the same behavior as type-variable usages have to Kotlin and to the Checker Framework.
 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},

 *       String}.
 *   <li>{@code getElement} on a {@code Multiset.Entry<@Nullable String>} returns {@code @Nullable
 *       String}.
 * </ul>
 *
 * This is the same behavior as type-variable usages have to Kotlin and to the Checker Framework.
 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},