///

## Without Pydantic

# Header Parameter Models

If you have a group of related **header parameters**, you can create a **Pydantic model** to declare them.

This would allow you to **re-use the model** in **multiple places** and also to declare validations and metadata for all the parameters at once. 😎

/// note

This is supported since FastAPI version `0.115.0`. 🤓

///

## Header Parameters with a Pydantic Model

    }

    protected String getContextId(MavenInvokerRequest<MavenOptions> invokerRequest) {
        // TODO: in a moment Maven stop pushing user properties to system properties (and maybe something more)
        // and allow multiple instances per JVM, this may become a pool?
        return "resident";
    }

    @Override
    protected void container(LocalContext context) throws Exception {
        if (context.containerCapsule == null) {

				</DelMarkerExpiration>
                            <Status>Enabled</Status>
	                    </Rule>`,
			expectedErr: errInvalidRuleDelMarkerExpiration,
		},
		{
			inputXML: `<Rule>
				<ID>Rule with multiple tags and DelMarkerExpiration</ID>
				<Filter><And>
				<Tag><Key>k1</Key><Value>v1</Value></Tag>
				<Tag><Key>k2</Key><Value>v2</Value></Tag>
				</And></Filter>
				<DelMarkerExpiration>
					<Days>365</Days>

import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;
import javax.annotation.CheckForNull;

/**
 * An {@link InputStream} that concatenates multiple substreams. At most one stream will be open at
 * a time.
 *
 * @author Chris Nokleberg
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault

<img src="/img/tutorial/bigger-applications/image01.png">

## Include the same router multiple times with different `prefix`

You can also use `.include_router()` multiple times with the *same* router using different prefixes.

This could be useful, for example, to expose the same API under different prefixes, e.g. `/api/v1` and `/api/latest`.

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

/// tip

To set multiple env vars for a single command just separate them with a space, and put them all before the command.

///

And then the `admin_email` setting would be set to `"******@****.***"`.

   *
   * <p>This is guaranteed to return zero if the dataset contains a single pair of finite values. It
   * is not guaranteed to return zero when the dataset consists of the same pair of values multiple
   * times, due to numerical errors.
   *
   * <h3>Non-finite values</h3>
   *
   * <p>If the dataset contains any non-finite values ({@link Double#POSITIVE_INFINITY}, {@link

USAGE:
  minio server [FLAGS] DIR1 [DIR2..]
  minio server [FLAGS] DIR{1...64}
  minio server [FLAGS] DIR{1...64} DIR{65...128}

DIR:
  DIR points to a directory on a filesystem. When you want to combine
  multiple drives into a single large system, pass one directory per
  filesystem separated by space. You may also use a '...' convention
  to abbreviate the directory arguments. Remote directories in a

   * e]}.
   */
  @Override
  String toString();

  // Refined Collection Methods

  /**
   * {@inheritDoc}
   *
   * <p>Elements that occur multiple times in the multiset will appear multiple times in this
   * iterator, though not necessarily sequentially.
   */
  @Override
  Iterator<E> iterator();

  /**
   * Determines whether this multiset contains the specified element.