Как изменить in_stock verbose_name?

Models.py

class Book(models.Model):
 name = models.CharField(u"Нэр", max_length = 200)

 @property
 def in_stock(self):
  return self.stocks.count()

Im Admin.py

class BookAdmin(admin.ModelAdmin):
 list_display  = ('name', 'in_stock')
 search_fields = ('name', )