{* ../../docs_src/dataclasses_/tutorial001_py310.py hl[1,6:11,18:19] *}

This is still supported thanks to **Pydantic**, as it has <a href="https://docs.pydantic.dev/latest/concepts/dataclasses/#use-of-stdlib-dataclasses-with-basemodel" class="external-link" target="_blank">internal support for `dataclasses`</a>.

I will show you some of the main concepts you should probably keep in mind when deploying a **FastAPI** application (although most of it applies to any other type of web application).

var baseErrs = []error{
	errDiskNotFound,
	errFaultyDisk,
	errFaultyRemoteDisk,
}

var baseIgnoredErrs = baseErrs

// Is a one place function which converts all os.PathError
// into a more FS object layer friendly form, converts
// known errors into their typed form for top level
// interpretation.
func osErrToFileErr(err error) error {
	if err == nil {
		return nil
	}
	if osIsNotExist(err) {

        dst[++dstIndex] = (byte) (val >>= 8);
        dst[++dstIndex] = (byte) (val >>= 8);
        dst[++dstIndex] = (byte) (val >> 8);
    }

    /**
     * Reads a Windows FILETIME value and converts it to Java time in milliseconds
     * @param src the source byte array
     * @param srcIndex the starting index in the source array
     * @return the time value in milliseconds since January 1, 1970 UTC
     */

import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;
import org.opensearch.core.common.Strings;

import com.ibm.icu.text.Transliterator;

/**
 * {@link KatakanaConverter} converts input strings to katakana representation.
 * It utilizes a transliterator to convert hiragana to katakana and can optionally
 * use a tokenizer to process the input.
 *
 * <p>

    String getId();

    /**
     * Gets the version number for this search log event.
     *
     * @return The version number, or null if not versioned
     */
    Long getVersionNo();

    /**
     * Converts this search log event to a source map for indexing or logging.
     *
     * @return Map representation of the event data
     */
    Map<String, Object> toSource();

    /**

        final OptionalEntity<SearchResponse> searchResponseOpt = sendRequest(query, params, userBean);
        return processResponse(searchResponseOpt);
    }

    /**
     * Processes the OpenSearch response and converts it to a SearchResult.
     *
     * @param searchResponseOpt the optional search response from OpenSearch
     * @return the processed search result
     */

Al desplegar aplicaciones probablemente querrás tener algo de **replicación de procesos** para aprovechar **múltiples núcleos** y poder manejar más requests.

Como viste en el capítulo anterior sobre [Conceptos de Despliegue](concepts.md){.internal-link target=_blank}, hay múltiples estrategias que puedes usar.

Aquí te mostraré cómo usar **Uvicorn** con **worker processes** usando el comando `fastapi` o el comando `uvicorn` directamente.

     */
    String getHostName();

    /**
     * Return the IP address as text such as "192.168.1.15".
     *
     * @return the ip address
     */
    String getHostAddress();

    /**
     * Converts this address to an InetAddress.
     *
     * @return this address as an InetAddress
     * @throws UnknownHostException if the host cannot be resolved
     */
    InetAddress toInetAddress() throws UnknownHostException;

	h.mu.RLock()
	defer h.mu.RUnlock()

	b, err := json.MarshalIndent(h, "", "  ")
	if err != nil {
		writer.Write([]byte(err.Error()))
		return
	}
	writer.Write(b)
}

// toHealingDisk converts the information to madmin.HealingDisk
func (h *healingTracker) toHealingDisk() madmin.HealingDisk {
	h.mu.RLock()
	defer h.mu.RUnlock()

	return madmin.HealingDisk{
		ID:                h.ID,