/// warning

If you are not an "expert" in OpenAPI, you probably don't need this.

///

You can set the OpenAPI `operationId` to be used in your *path operation* with the parameter `operation_id`.

You would have to make sure that it is unique for each operation.

{* ../../docs_src/path_operation_advanced_configuration/tutorial001_py310.py hl[6] *}

## What makes a dependency { #what-makes-a-dependency }

Up to now you have seen dependencies declared as functions.

But that's not the only way to declare dependencies (although it would probably be the more common).

The key factor is that a dependency should be a "callable".

A "**callable**" in Python is anything that Python can "call" like a function.

* Data validation
* Automatic documentation

## Defaults { #defaults }

As query parameters are not a fixed part of a path, they can be optional and can have default values.

In the example above they have default values of `skip=0` and `limit=10`.

So, going to the URL:

```
http://127.0.0.1:8000/items/
```

would be the same as going to:

```

```JSON
{
    "item": {
        "name": "Foo",
        "description": "The pretender",
        "price": 42.0,
        "tax": 3.2
    },
    "user": {
        "username": "dave",
        "full_name": "Dave Grohl"
    }
}
```

/// note | Заметка

Обратите внимание, что хотя параметр `item` был объявлен таким же способом, как и раньше, теперь предполагается, что он находится внутри тела с ключом `item`.

	// Total Size for objects that have not yet been replicated
	ReplicationPendingSizeV1 uint64 `json:"objectsPendingReplicationTotalSize"`
	// Total size for objects that have witness one or more failures and will be retried
	ReplicationFailedSizeV1 uint64 `json:"objectsFailedReplicationTotalSize"`
	// Total size for objects that have been replicated to destination

   *
   * <p>Thus, two value graphs A and B are equal if <b>all</b> of the following are true:
   *
   * <ul>
   *   <li>A and B have equal {@link #isDirected() directedness}.
   *   <li>A and B have equal {@link #nodes() node sets}.
   *   <li>A and B have equal {@link #edges() edge sets}.
   *   <li>The {@link #edgeValueOrDefault(N, N, V) value} of a given edge is the same in both A and
   *       B.
   * </ul>

 *
 * <p>Keep a strong reference to this object until all of the associated referents have been
 * finalized. If this object is garbage collected earlier, the backing thread will not invoke {@code
 * finalizeReferent()} on the remaining references.
 *
 * <p>As an example of how this is used, imagine you have a class {@code MyServer} that creates a

      headersQueue += headers
    } else {
      check(isLocallyInitiated) { "remotely-initiated streams should have headers" }
    }
  }

  /**
   * Returns true if this stream is open. A stream is open until either:
   *
   *  * A `SYN_RESET` frame abnormally terminates the stream.
   *  * Both input and output streams have transmitted all data and headers.
   *

    tests, either. This causes it to fail to find AtomicLongMapTest.

    Our workaround is to tell GWT that util.concurrent and all other packages
    have prod supersource, even if they have none. GWT is happy to ignore us
    when we specify a nonexistent path.

    (I hope that this workaround does not cause its own problems in the future.)
-->
<super-source path="super"/>

    tests, either. This causes it to fail to find AtomicLongMapTest.

    Our workaround is to tell GWT that util.concurrent and all other packages
    have prod supersource, even if they have none. GWT is happy to ignore us
    when we specify a nonexistent path.

    (I hope that this workaround does not cause its own problems in the future.)
-->
<super-source path="super"/>