new_contents: # -*- coding: utf-8 -*-
  from decimal import Decimal as D
  
  from django.utils.translation import ugettext_lazy as _
  
  OSCAR_SHIPPING_WEIGHT_PRECISION = D('0.000')
  
  OSCAR_SHIPPING_VOLUME_PRECISION = D('0.000') 
  
  # per product defaults
  # 0.1m x 0.1m x 0.1m
  OSCAR_SHIPPING_DEFAULT_BOX = {'width' : float('0.1'), 
                                'height' : float('0.1'), 
                                'lenght' : float('0.1') }
  
  # 1 Kg 
  OSCAR_SHIPPING_DEFAULT_WEIGHT = 1 
  
  # basket volue * VOLUME_RATIO = estimated container(s) volume
  # very simple method
  OSCAR_SHIPPING_VOLUME_RATIO = D('1.3')
  
  #default city of origin to calculate shipping cost via APIs
  OSCAR_SHIPPING_DEFAULT_ORIGIN = u'Санкт-Петербург'
  
  OSCAR_SHIPPING_API_ENABLED = ['pecom', 'emspost']
subject: Implement defaults.py which contains all default settings, such as weight and volume precision values, default origin and packer opts. Do not forget to include it in the project settings module : `from oscar_shipping.defaults import *`