checkCleanDirWindows(
                    "%teamcity.agent.jvm.user.home%\\.android",
                    false
                )
        } else {
            checkCleanDirUnixLike("%teamcity.agent.jvm.user.home%/.m2/repository") +
                checkCleanDirUnixLike("%teamcity.agent.jvm.user.home%/.m2/.gradle-enterprise") +

from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: Union[bool, None] = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}


@app.put("/items/{item_id}")

Поскольку по умолчанию, отдельные значения интерпретируются как query-параметры, вам не нужно явно добавлять `Query`, вы можете просто сделать так:

```Python
q: Union[str, None] = None
```

Или в Python 3.10 и выше:

```Python
q: str | None = None
```

Например:

=== "Python 3.10+"

    ```Python hl_lines="27"
    {!> ../../../docs_src/body_multiple_params/tutorial004_an_py310.py!}
    ```

  // An object that describes the pod that will be created.
  // The DaemonSet will create exactly one copy of this pod on every node
  // that matches the template's node selector (or on every node if no node
  // selector is specified).
  // The only allowed template.spec.restartPolicy value is "Always".

  // An object that describes the pod that will be created.
  // The DaemonSet will create exactly one copy of this pod on every node
  // that matches the template's node selector (or on every node if no node
  // selector is specified).
  // More info: https://kubernetes.io/docs/concepts/workloads/controllers/replicationcontroller#pod-template

from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: Union[bool, None] = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}


@app.put("/items/{item_id}")

from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: Union[bool, None] = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}


@app.put("/items/{item_id}")

from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: Union[bool, None] = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}


@app.put("/items/{item_id}")

import okhttp3.internal.http2.Http2.FLAG_ACK
import okhttp3.internal.http2.Http2.FLAG_END_HEADERS
import okhttp3.internal.http2.Http2.FLAG_END_STREAM
import okhttp3.internal.http2.Http2.FLAG_NONE
import okhttp3.internal.http2.Http2.INITIAL_MAX_FRAME_SIZE
import okhttp3.internal.http2.Http2.TYPE_CONTINUATION
import okhttp3.internal.http2.Http2.TYPE_DATA
import okhttp3.internal.http2.Http2.TYPE_GOAWAY

    ```

=== "Python 3.8+"

    ```Python hl_lines="11  13-14"
    {!> ../../../docs_src/response_model/tutorial004.py!}
    ```

* `description: Union[str, None] = None` (или `str | None = None` в Python 3.10), где `None` является значением по умолчанию.
* `tax: float = 10.5`, где `10.5` является значением по умолчанию.
* `tags: List[str] = []`, где пустой список `[]` является значением по умолчанию.