如何向InlineFormsets添加自定义字段？

from django.db import models
from django.forms import Textarea
from django.contrib import admin

class Author(models.Model):
    name = models.CharField(max_length=100)

class Book(models.Model):
    title = models.CharField(max_length=100)
    author = models.ForeignKey(Author, on_delete=models.CASCADE)

class BookInline(admin.TabularInline):  # 或者使用 admin.StackedInline
    model = Book
    extra = 1

from django.contrib import admin
from .models import Author, Book

class BookInline(admin.TabularInline):
    model = Book
    extra = 1

class AuthorAdmin(admin.ModelAdmin):
    inlines = [
        BookInline,
    ]

admin.site.register(Author, AuthorAdmin)

from django import forms
from django.contrib import admin
from .models import Author, Book

class BookInlineForm(forms.ModelForm):
    class Meta:
        model = Book
        fields = '__all__'
        widgets = {
            'title': Textarea(attrs={'rows': 2, 'cols': 40}),
        }

class BookInline(admin.TabularInline):
    model = Book
    extra = 1
    form = BookInlineForm

class AuthorAdmin(admin.ModelAdmin):
    inlines = [
        BookInline,
    ]

admin.site.register(Author, AuthorAdmin)