In this case, it's a list of `Item` dataclasses.

6. Here we are returning a dictionary that contains `items` which is a list of dataclasses.

    FastAPI is still capable of <abbr title="converting the data to a format that can be transmitted">serializing</abbr> the data to JSON.

7. Here the `response_model` is using a type annotation of a list of `Author` dataclasses.

    * JSON.
    * Pad parameters.
    * Query parameters.
    * Cookies.
    * Headers.
    * Formulieren.
    * Bestanden.
* <abbr title="ook bekend als: serialisatie, parsing, marshalling">Conversie</abbr> van uitvoergegevens: converstie van Python-data en -types naar netwerkgegevens (zoals JSON):

{"item_id":3}
```

/// check

Notice that the value your function received (and returned) is `3`, as a Python `int`, not a string `"3"`.

So, with that type declaration, **FastAPI** gives you automatic request <abbr title="converting the string that comes from an HTTP request into Python data">"parsing"</abbr>.

///

## Data validation

        };
    Function<Object, String> backward = toStringFunction();

    Converter<String, Number> converter = Converter.<String, Number>from(forward, backward);

    assertNull(converter.convert(null));
    assertNull(converter.reverse().convert(null));

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

            "msg": "value is not a valid integer",
            "type": "type_error.integer"
        }
    ]
}
```

car le paramètre de chemin `item_id` possède comme valeur `"foo"`, qui ne peut pas être convertie en entier (`int`).

La même erreur se produira si vous passez un nombre flottant (`float`) et non un entier, comme ici

import org.codehaus.plexus.component.configurator.converters.ConfigurationConverter;
import org.codehaus.plexus.component.configurator.converters.composite.ObjectWithFieldsConverter;
import org.codehaus.plexus.component.configurator.converters.lookup.ConverterLookup;
import org.codehaus.plexus.component.configurator.converters.lookup.DefaultConverterLookup;

class EnhancedConverterLookup implements ConverterLookup {

            put(convertKey(entry.getKey()), entry.getValue());
        }
    }

    @Override
    public final V remove(final Object key) {
        return super.remove(convertKey(key));
    }

    @Override
    public boolean containsKey(final Object key) {
        return super.containsKey(convertKey(key));
    }

    private static String convertKey(final Object key) {

    public String toString() {
        return new String( "NetShareEnumResponse[" +
                super.toString() +
                ",status=" + status +
                ",converter=" + converter +
                ",entriesReturned=" + numEntries +
                ",totalAvailableEntries=" + totalAvailableEntries + "]" );
    }

  public void testStringConverter_convert() {
    Converter<String, TestEnum> converter = Enums.stringConverter(TestEnum.class);
    assertEquals(TestEnum.CHEETO, converter.convert("CHEETO"));
    assertEquals(TestEnum.HONDA, converter.convert("HONDA"));
    assertEquals(TestEnum.POODLE, converter.convert("POODLE"));
    assertNull(converter.convert(null));
    assertNull(converter.reverse().convert(null));
  }

    final ClassMetaDataRepository<ClassMetaData> repository = Mock()
    final GenerationListener listener = Mock()
    final JavadocLinkConverter converter = new JavadocLinkConverter(document, nameResolver, linkRenderer, repository)

    def convertsClassNameToLink() {
        when:
        def link = converter.resolve('someName', classMetaData, listener)

        then:
        format(link) == '<someLinkElement/>'