django admin编辑被外键关联的主表时支持显示字表记录

假设有模型

class A(models.Model):
        name = models.CharField()

class B(models.Model):
        name = models.CharField()
        a    = models.ForeignKey(A) 

如果想要在django admin 后台编辑A表记录时，能同时关联相应的B表记录，

class BAdmin(admin.ModelAdmin):

    list_display = ['a__name', ]

class BInline(admin.StackedInline):
    model = B


class AAdmin(admin.ModelAdmin):
    inlines = [BInline, ]