app = FastAPI()

    class ModelB(BaseModel):
        username: str

    class ModelC(ModelB):
        password: str

    class ModelA(BaseModel):
        name: str
        description: Optional[str] = None
        foo: ModelB
        tags: dict[str, str] = {}

        @field_validator("name")
        def lower_username(cls, name: str, info: ValidationInfo):
            if not name.endswith("A"):

	defer callhomeTimer.Stop()

	for {
		if !globalCallhomeConfig.Enabled() {
			// Stop the processing as callhome got disabled
			return false
		}

		select {
		case <-ctx.Done():
			// indicates that we do not need to run callhome anymore
			return false
		case <-callhomeTimer.C:
			if !globalCallhomeConfig.Enabled() {
				// Stop the processing as callhome got disabled
				return false

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *

    opt Raise other exception
        tasks -->> tasks: Handle exceptions in the background task code
    end
```

/// info

Only **one response** will be sent to the client. It might be one of the error responses or it will be the response from the *path operation*.

After one of those responses is sent, no other response can be sent.

///

/// tip

///

/// check

OpenAPI specifies that each *path operation* requires a response description.

So, if you don't provide one, **FastAPI** will automatically generate one of "Successful response".

///

<img src="/img/tutorial/path-operation-configuration/image03.png">

## Deprecate a *path operation* { #deprecate-a-path-operation }

        .any(gradle.startParameter.taskNames::contains)


/**
 * Returns a new provider that takes its value from at most one
 * of the given providers. If no input provider is present, the output
 * provider will not be present. If more than one input provider
 * has a value specified, the resulting provider will throw an
 * exception when queried.
 */

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *

            {"name": "Bar", "description": "The bartenders", "price": 62, "tax": 20.2},
        ),
        (
            "/items/baz",
            {
                "name": "Baz",
                "description": None,
                "price": 50.2,
                "tax": 10.5,
                "tags": [],
            },
        ),
    ],
)
def test_get(url, data, client: TestClient):
    response = client.get(url)

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *