## List fields { #list-fields }

You can define an attribute to be a subtype. For example, a Python `list`:

{* ../../docs_src/body_nested_models/tutorial001_py310.py hl[12] *}

This will make `tags` be a list, although it doesn't declare the type of the elements of the list.

## List fields with type parameter { #list-fields-with-type-parameter }

But Python has a specific way to declare lists with internal types, or "type parameters":

import okio.Buffer
import org.junit.jupiter.api.AfterEach
import org.junit.jupiter.api.Disabled
import org.junit.jupiter.api.Test

/**
 * Access every declaration that is deprecated with [DeprecationLevel.ERROR]. Although new Kotlin
 * code shouldn't use these, they're necessary for clients migrating from OkHttp 3.x and this test
 * ensures the symbols remain available and with the expected parameter and return types.
 */
@Suppress(

     * Return the <code>InputStream</code> used to read information
     * from this pipe instance. Presumably data would first be written
     * to the <code>OutputStream</code> associated with this Named
     * Pipe instance although this is not a requirement (e.g. a
     * read-only named pipe would write data to this stream on
     * connection). Reading from this stream may block. Therefore it

We will try to fix the problems as soon as possible. Vulnerabilities will, in
general, be batched to be fixed at the same time as a quarterly release. We
credit reporters for identifying security issues, although we keep your name
confidential if you request it. Please see Google Bug Hunters program website

{* ../../docs_src/path_operation_advanced_configuration/tutorial007_py310.py hl[15:20, 22] *}

Nevertheless, although we are not using the default integrated functionality, we are still using a Pydantic model to manually generate the JSON Schema for the data that we want to receive in YAML.

   * method may return before refresh completes.
   *
   * @since 11.0
   */
  @GwtIncompatible
  @J2ktIncompatible
  void refresh(K key);

  /**
   * {@inheritDoc}
   *
   * <p><b>Note that although the view <i>is</i> modifiable, no method on the returned map will ever
   * cause entries to be automatically loaded.</b>
   */
  @Override
  @J2ktIncompatible
  ConcurrentMap<K, V> asMap();

We can do better...

## 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.

 *
 * <p>While {@code ReadWriteLock} instances have different properties and can form cycles without
 * potential deadlock, this class treats {@code ReadWriteLock} instances as equivalent to
 * traditional exclusive locks. Although this increases the false positives that the locks detect
 * (i.e. cycles that will not actually result in deadlock), it simplifies the algorithm and

   * method may return before refresh completes.
   *
   * @since 11.0
   */
  @GwtIncompatible
  @J2ktIncompatible
  void refresh(K key);

  /**
   * {@inheritDoc}
   *
   * <p><b>Note that although the view <i>is</i> modifiable, no method on the returned map will ever
   * cause entries to be automatically loaded.</b>
   */
  @Override
  @J2ktIncompatible
  ConcurrentMap<K, V> asMap();

* `description`: A long description that can contain Markdown text.
* `value`: This is the actual example shown, e.g. a `dict`.
* `externalValue`: alternative to `value`, a URL pointing to the example. Although this might not be supported by as many tools as `value`.

You can use it like this:

{* ../../docs_src/schema_extra_example/tutorial005_an_py310.py hl[23:49] *}