old_contents: from django.contrib import admin
  
  from users.models import Lageruser, Department, DepartmentUser
  
  
  admin.site.register(Lageruser)
  admin.site.register(Department)
  admin.site.register(DepartmentUser)
new_contents: from django.contrib import admin
  
  from users.models import Lageruser, Department, DepartmentUser
  
  class LageruserAdmin(admin.ModelAdmin):
      search_fields = ('first_name', 'last_name', )
  
  admin.site.register(Lageruser, LageruserAdmin)
  admin.site.register(Department)
  admin.site.register(DepartmentUser)
  
subject: make user list in admin/ searchable