{* ../../docs_src/separate_openapi_schemas/tutorial001_py310.py ln[1:15] hl[14] *}

...then the `description` field will **not be required**. Because it has a default value of `None`.

### Input Model in Docs { #input-model-in-docs }

You can confirm that in the docs, the `description` field doesn't have a **red asterisk**, it's not marked as required:

<div class="screenshot">

from __future__ import annotations

import uuid
from dataclasses import dataclass, field
from typing import Union

from dirty_equals import IsUUID
from fastapi import FastAPI
from fastapi.testclient import TestClient
from inline_snapshot import snapshot


@dataclass
class Item:
    id: uuid.UUID
    name: str
    price: float
    tags: list[str] = field(default_factory=list)
    description: Union[str, None] = None

		DeleteClauses:        []string{"DELETE", "FROM", "WHERE", "RETURNING"},
		LastInsertIDReversed: true,
	})

	return nil
}

func (DummyDialector) DefaultValueOf(field *schema.Field) clause.Expression {
	return clause.Expr{SQL: "DEFAULT"}
}

func (DummyDialector) Migrator(*gorm.DB) gorm.Migrator {
	return nil
}

func (z *listPathOptions) DecodeMsg(dc *msgp.Reader) (err error) {
	var field []byte
	_ = field
	var zb0001 uint32
	zb0001, err = dc.ReadMapHeader()
	if err != nil {
		err = msgp.WrapError(err)
		return
	}
	for zb0001 > 0 {
		zb0001--
		field, err = dc.ReadMapKeyPtr()
		if err != nil {
			err = msgp.WrapError(err)
			return
		}
		switch msgp.UnsafeString(field) {
		case "ID":
			z.ID, err = dc.ReadString()

                }
            }

        } else if (member instanceof JApiField) {

            JApiField field = (JApiField) member
            CtField oldField = field.oldFieldOptional.get()
            CtField newField = field.newFieldOptional.get()

            def oldNullability = nullabilityOf(oldField)
            def newNullability = nullabilityOf(newField)

		// Test case with invalid credential field.
		{
			inputV4AuthStr:    signV4Algorithm + " Cred=,a,b",
			expectedAuthField: signValues{},
			expectedErrCode:   ErrMissingCredTag,
		},
		// Test case - 5.
		// Auth field with missing "SigHeaderTag",ErrMissingSignHeadersTag expected.
		// A valid credential is generated.
		// Test case with invalid credential field.
		{
			inputV4AuthStr: signV4Algorithm +

        "detail": [
            {
                "loc": ["body", "name"],
                "input": {},
                "msg": "Field required",
                "type": "missing",
            },
            {
                "loc": ["body", "price"],
                "input": {},
                "msg": "Field required",
                "type": "missing",
            },
        ]
    }

 * the License.
 */

package com.google.common.util.concurrent;

import static java.lang.annotation.ElementType.CONSTRUCTOR;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.TYPE;

import java.lang.annotation.Target;

/**

 * the License.
 */

package com.google.common.cache;

import static java.lang.annotation.ElementType.CONSTRUCTOR;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.TYPE;

import java.lang.annotation.Target;

/**

    extends AggregateFuture<V, C> {
  /*
   * We access this field racily but safely. For discussion of a similar situation, see the comments
   * on the fields of TimeoutFuture. This field is slightly different from the fields discussed
   * there: cancel() never reads this field, only writes to it. That makes the race here completely
   * harmless, rather than just 99.99% harmless.
   */