}
			// Failed as expected, but does it fail for the expected reason.
			if err != nil && !testCase.shouldPass {
				if !strings.Contains(err.Error(), testCase.err.Error()) {
					t.Errorf("Test %d: %s: Expected to fail with error \"%s\", but instead failed with error \"%s\" instead", i+1, instanceType, testCase.err.Error(), err.Error())
				}

The syntax `{"name", "description"}` creates a `set` with those two values.

It is equivalent to `set(["name", "description"])`.

///

#### Using `list`s instead of `set`s { #using-lists-instead-of-sets }

If you forget to use a `set` and use a `list` or `tuple` instead, FastAPI will still convert it to a `set` and it will work correctly:

{* ../../docs_src/response_model/tutorial006_py310.py hl[29,35] *}

## Recap { #recap }

# Form Data { #form-data }

When you need to receive form fields instead of JSON, you can use `Form`.

/// info

To use forms, first install <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a>.

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then install it, for example:

```console
$ pip install python-multipart
```

 * }
 *
 * Instead, you can pass a lambda expression to the {@code using} factory method:
 *
 * {@snippet :
 * TreeTraverser<NodeType> traverser = TreeTraverser.using(node -> node.getChildNodes());
 * }
 *
 * @author Louis Wasserman
 * @since 15.0
 * @deprecated Use {@link com.google.common.graph.Traverser} instead. All instance methods have

     * readable name.
     */
    @CanIgnoreReturnValue
    public ToStringHelper addValue(@Nullable Object value) {
      return addHolder(value);
    }

    /**
     * Adds an unnamed value to the formatted output.
     *
     * <p>It is strongly encouraged to use {@link #add(String, boolean)} instead and give value a
     * readable name.
     *

   * however, {@code asMap().get(Object)} returns {@code null} instead of an empty collection.
   *
   * <p><b>Note:</b> The returned map's values are guaranteed to be of type {@link SortedSet}. To
   * obtain this map with the more specific generic type {@code Map<K, SortedSet<V>>}, call {@link
   * Multimaps#asMap(SortedSetMultimap)} instead. <b>However</b>, the returned map <i>itself</i> is

	// location of the Modified time.
	Modified time.Time

	// ModifiedTime is an MS-DOS-encoded time.
	//
	// Deprecated: Use Modified instead.
	ModifiedTime uint16

	// ModifiedDate is an MS-DOS-encoded date.
	//
	// Deprecated: Use Modified instead.
	ModifiedDate uint16

	// CRC32 is the CRC32 checksum of the file content.
	CRC32 uint32

		},
	}

	// Run each test case individually.
	for i, testCase := range testCases {
		_, code := doesPolicySignatureMatch(testCase.form)
		if code != testCase.expected {
			t.Errorf("(%d) expected to get %s, instead got %s", i, niceError(testCase.expected), niceError(code))
		}
	}
}

func TestDoesPresignedSignatureMatch(t *testing.T) {
	ctx, cancel := context.WithCancel(t.Context())
	defer cancel()

  public @Nullable B put(TypeToken<? extends @NonNull B> key, @ParametricNullness B value) {
    throw new UnsupportedOperationException("Please use putInstance() instead.");
  }

  /**
   * Not supported. Use {@link #putInstance} instead.
   *
   * @deprecated unsupported operation
   * @throws UnsupportedOperationException always
   */
  @Deprecated
  @Override
  @DoNotCall("Always throws UnsupportedOperationException")

   * E} is an {@link Enum} type, use {@link EnumSet#noneOf} instead. Otherwise, strongly consider
   * using a {@code LinkedHashSet} instead, at the cost of increased memory footprint, to get
   * deterministic iteration behavior.
   *
   * <p><b>Note:</b> this method is now unnecessary and should be treated as deprecated. Instead,