old_contents: from django.contrib import admin
  from oscar.core.loading import get_model
  
  
  class UserAddressAdmin(admin.ModelAdmin):
      readonly_fields = ('num_orders',)
  
  
  admin.site.register(get_model('address', 'useraddress'), UserAddressAdmin)
  admin.site.register(get_model('address', 'country'))
  
new_contents: from django.contrib import admin
  from oscar.core.loading import get_model
  
  
  class UserAddressAdmin(admin.ModelAdmin):
      readonly_fields = ('num_orders',)
  
  
  class CountryAdmin(admin.ModelAdmin):
      search_fields = ('name',)
  
  
  admin.site.register(get_model('address', 'useraddress'), UserAddressAdmin)
  admin.site.register(get_model('address', 'country'), CountryAdmin)
  
subject: Make countries searchable in Django admin