只要您不介意访问 ModelAdmin 上的"private"属性，就可以非常简单地完成此操作.(以下划线开头的属性按照惯例被视为私有.)

You can do this pretty simply, providing you don't mind accessing a 'private' attribute on the ModelAdmin. (Attributes beginning with an underscore are treated as private by convention.)

# two/admin.py
from django.contrib import admin
from one.models import One
from .models import Two

class TwoInline(admin.StackedInline):
    model = Two

admin.site._registry[One].inlines.append(TwoInline)