So, the prefix in this case is `/items`.

We can also add a list of `tags` and extra `responses` that will be applied to all the *path operations* included in this router.

And we can add a list of `dependencies` that will be added to all the *path operations* in the router and will be executed/solved for each request made to them.

/// tip

                be a Pydantic model, it could be other things, like a `list`, `dict`,
                etc.

                It will be used for:

                * Documentation: the generated OpenAPI (and the UI at `/docs`) will
                    show it as the response (JSON Schema).
                * Serialization: you could return an arbitrary object and the

 * is {@link org.apache.maven.api.Node Node} and {@code pathScope == ""},
 * then the dependencies will be <i>collected</i>.
 * If the type is {@link org.apache.maven.api.Node Node} or
 * {@code List<}{@link org.apache.maven.api.Node Node}{@code >},
 * and {@code pathScope != ""}, the dependencies will be <i>flattened</i>.
 * Else the dependencies will be <i>resolved</i> and {@code pathScope} must be non empty,

   * loaded entries; it will never contain null keys or values.
   *
   * <p>Caches loaded by a {@link CacheLoader} will issue a single request to {@link
   * CacheLoader#loadAll} for all keys which are not already present in the cache. All entries
   * returned by {@link CacheLoader#loadAll} will be stored in the cache, over-writing any
   * previously cached values. This method will throw an exception if {@link CacheLoader#loadAll}

### Server Memory { #server-memory }

For example, if your code loads a Machine Learning model with **1 GB in size**, when you run one process with your API, it will consume at least 1 GB of RAM. And if you start **4 processes** (4 workers), each will consume 1 GB of RAM. So in total, your API will consume **4 GB of RAM**.

   * captured by the returned {@link ClosingFuture}).
   *
   * <p>If this {@code ClosingFuture} succeeds, the derived one will be equivalent to the one
   * returned by the function.
   *
   * <p>If this {@code ClosingFuture} fails, the function will not be called, and the derived {@code
   * ClosingFuture} will be equivalent to this one.
   *
   * <p>If the function throws an exception, that exception is used as the result of the derived

///

The dependencies will keep working as expected, and the **best part** is that the **type information will be preserved**, which means that your editor will be able to keep providing you with **autocompletion**, **inline errors**, etc. The same for other tools like `mypy`.

You can define logic (code) that should be executed before the application **starts up**. This means that this code will be executed **once**, **before** the application **starts receiving requests**.

The same way, you can define logic (code) that should be executed when the application is **shutting down**. In this case, this code will be executed **once**, **after** having handled possibly **many requests**.

The response object will also have autocompletion:

<img src="/img/tutorial/generate-clients/image05.png">

## FastAPI App with Tags { #fastapi-app-with-tags }

In many cases, your FastAPI app will be bigger, and you will probably use tags to separate different groups of *path operations*.

For example, you could have a section for **items** and another section for **users**, and they could be separated by tags:

meaning that reads and writes will return immediately with an error if the operation cannot be completed.
If you want to block when reading or writing, you must enable it:

```go
	rb := ringbuffer.New(1024).SetBlocking(true)
```

Enabling blocking will cause the ring buffer to behave like a buffered [io.Pipe](https://pkg.go.dev/io#Pipe).

Regular Reads will block until data is available, but not wait for a full buffer.