* «autocomplete»: «autocomplétion»
* «autocompletion»: «autocomplétion»

* «the request» (what the client sends to the server): «la requête»
* «the response» (what the server sends back to the client): «la réponse»

* «the request body»: «le corps de la requête»
* «the response body»: «le corps de la réponse»

* «path operation»: «opération de chemin»
* «path operations» (plural): «opérations de chemin»

@pytest.mark.parametrize(
    "path",
    ["/optional-str", "/model-optional-str"],
)
def test_optional_str_schema(path: str):
    assert app.openapi()["paths"][path]["get"]["parameters"] == [
        {
            "required": False,
            "schema": {
                "anyOf": [{"type": "string"}, {"type": "null"}],
                "title": "P",
            },
            "name": "p",
            "in": "header",
        }
    ]

   * because underutilization = free resources for the taking. If we are primarily interested to
   * deal with overflow, then stored permits could be given out /slower/ than fresh ones. Thus, we
   * require a (different in each case) function that translates storedPermits to throttling time.
   *
   * This role is played by storedPermitsToWaitTime(double storedPermits, double permitsToTake). The

                    "summary": "Save Item No Body",
                    "operationId": "save_item_no_body_items__item_id__put",
                    "parameters": [
                        {
                            "required": True,
                            "schema": {"title": "Item Id", "type": "string"},
                            "name": "item_id",
                            "in": "path",
                        }
                    ],

                        "summary": "Read Items",
                        "operationId": "read_items_items__item_id__get",
                        "parameters": [
                            {
                                "required": True,
                                "schema": {"title": "Item Id", "type": "string"},
                                "name": "item_id",
                                "in": "path",
                            }

 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the

                }
            },
        },
        "components": {
            "schemas": {
                "Error": {
                    "title": "Error",
                    "required": ["status", "title"],
                    "type": "object",
                    "properties": {
                        "status": {"title": "Status", "type": "string"},

 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the

        Modifications to the build process which is keyed on some
        sort of environmental parameter.
      ]]></description>
      <fields>
        <field>
          <name>id</name>
          <required>true</required>
          <version>1.0.0</version>
          <type>String</type>
          <description>The ID of this build profile, for activation
            purposes.</description>
        </field>
        <field>

/// note

FastAPI will know that the value of `q` is not required because of the default value `= None`.

The `str | None` (Python 3.10+) or `Union` in `Union[str, None]` (Python 3.9+) is not used by FastAPI to determine that the value is not required, it will know it's not required because it has a default value of `= None`.