```

////

The query parameter `q` is of type `Union[str, None]` (or `str | None` in Python 3.10), that means that it's of type `str` but could also be `None`, and indeed, the default value is `None`, so FastAPI will know it's not required.

/// note

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

The `Union` in `Union[str, None]` will allow your editor to give you better support and detect errors.

```

</div>

## In Detail

The marker `@pytest.mark.anyio` tells pytest that this test function should be called asynchronously:

{* ../../docs_src/async_tests/test_main.py hl[7] *}

/// tip

Note that the test function is now `async def` instead of just `def` as before when using the `TestClient`.

///

Then we can create an `AsyncClient` with the app, and send async requests to it, using `await`.

```Python hl_lines="19-24  28"
{!../../docs_src/additional_responses/tutorial002.py!}
```

/// note

- 请注意，您必须直接使用 `FileResponse` 返回图像。

///

/// info

- 除非在 `responses` 参数中明确指定不同的媒体类型，否则**FastAPI**将假定响应与主响应类具有相同的媒体类型（默认为` application/json` ）。
- 但是如果您指定了一个自定义响应类，并将 `None `作为其媒体类型，**FastAPI**将使用 `application/json` 作为具有关联模型的任何其他响应。

///

## 组合信息

# Set enableTracing to false to disable request tracing.
enableTracing: true
# This is the ingress service name, update if you used a different name
ingressService: istio-ingress
#
defaultConfig:
  # NOTE: If you change any values in this section, make sure to make
  # the same changes in start up args in istio-ingress pods.
  #
  # TCP connection timeout between Envoy & the application, and between Envoys.
  connectTimeout: 1s
  #

buckets: # # Name of the bucket # - name: bucket1 # # Policy to be set on the # # bucket [none|download|upload|public] # policy: none # # Purge if bucket exists already # purge: false # # set versioning for # # bucket [true|false] # versioning: false # # set objectlocking for # # bucket [true|false] NOTE: versioning is enabled by default if you use locking # objectlocking: false # - name: bucket2 # policy: none # purge: false # versioning: true # # set objectlocking for # # bucket [true|false] NOTE:...

buckets: # # Name of the bucket # - name: bucket1 # # Policy to be set on the # # bucket [none|download|upload|public] # policy: none # # Purge if bucket exists already # purge: false # # set versioning for # # bucket [true|false] # versioning: false # # set objectlocking for # # bucket [true|false] NOTE: versioning is enabled by default if you use locking # objectlocking: false # - name: bucket2 # policy: none # purge: false # versioning: true # # set objectlocking for # # bucket [true|false] NOTE:...

buckets: [] # # Name of the bucket # - name: bucket1 # # Policy to be set on the # # bucket [none|download|upload|public] # policy: none # # Purge if bucket exists already # purge: false # # set versioning for # # bucket [true|false] # versioning: false # # set objectlocking for # # bucket [true|false] NOTE: versioning is enabled by default if you use locking # objectlocking: false # - name: bucket2 # policy: none # purge: false # versioning: true # # set objectlocking for # # bucket [true|false] NOTE:...

buckets: # # Name of the bucket # - name: bucket1 # # Policy to be set on the # # bucket [none|download|upload|public] # policy: none # # Purge if bucket exists already # purge: false # # set versioning for # # bucket [true|false] # versioning: false # # set objectlocking for # # bucket [true|false] NOTE: versioning is enabled by default if you use locking # objectlocking: false # - name: bucket2 # policy: none # purge: false # versioning: true # # set objectlocking for # # bucket [true|false] NOTE:...

		},
		"idx_user_indices_name8": {
			Name: "idx_user_indices_name8",
			Type: "",
			Fields: []schema.IndexOption{
				{Field: &schema.Field{Name: "Name8"}, Length: 10},
				// Note: Duplicate Columns
				{Field: &schema.Field{Name: "Name8"}, Collate: "utf8"},
			},
		},
		"idx_user_indices_comp_id0": {
			Name: "idx_user_indices_comp_id0",
			Type: "",
			Fields: []schema.IndexOption{{

## NOTE

- Empty delete markers (such as for objects with no other successor versions) do not transition to the new pool to avoid creating empty metadata on the other pool(s). If you believe transitioning empty delete markers is required, open a GitHub issue.

## TODO