old_contents: from django.contrib import admin
  from django.db import models
  from django.forms.widgets import TextInput
  
  
  class AbstractSellingPointAdmin(admin.ModelAdmin):
      """name your foreign key to product model "product" in order to fully utilize this class"""
      search_fields = ['text', 'product__name', 'product__item_number',]
      list_display = ['product', 'text',]
      raw_id_fields = ['product',]
      formfield_overrides = {
          models.CharField: {'widget': TextInput(attrs={'size': '150'})},
      }
  
  
  class AbstractWashingInstructionAdmin(admin.ModelAdmin):
      list_display = ['text', 'render_icon',]
      search_fields = ['text',]
  
  
new_contents: from django.contrib import admin
  from django.db import models
  from django.forms.widgets import TextInput
  
  
  class AbstractSellingPointAdmin(admin.ModelAdmin):
      """name your foreign key to product model "product" in order to fully utilize this class"""
      search_fields = ['text', 'product__name', 'product__item_number',]
      list_display = ['product', 'text',]
      raw_id_fields = ['product',]
      formfield_overrides = {
          models.CharField: {'widget': TextInput(attrs={'size': '150'})},
      }
  
  
  class AbstractWashingInstructionAdmin(admin.ModelAdmin):
      list_display = ['text', 'render_icon',]
      search_fields = ['text',]
  
  
  class AbstractProductWashingInstructionAdmin(admin.ModelAdmin):
      list_display = ['product', 'washing_instruction',]
      raw_id_fields = ['product',]
  
  
subject: add AbstractProductWashingInstructionAdmin