code: def add(self, num_iid, properties, quantity, price, session, outer_id=None, item_price=None, lang=None):
          '''taobao.item.sku.add 添加SKU
          
          新增一个sku到num_iid指定的商品中 传入的iid所对应的商品必须属于当前会话的用户'''
          request = TOPRequest('taobao.item.sku.add')
          request['num_iid'] = num_iid
          request['properties'] = properties
          request['quantity'] = quantity
          request['price'] = price
          if outer_id!=None:
              request['outer_id'] = outer_id
          if item_price!=None:
              request['item_price'] = item_price
          if lang!=None:
              request['lang'] = lang
          self.create(self.execute(request, session)['sku'])
          return self add(self, num_iid, properties, quantity, price, session, outer_id=None, item_price=None, lang=None):
          '''taobao.item.sku.add 添加SKU
          
          新增一个sku到num_iid指定的商品中 传入的iid所对应的商品必须属于当前会话的用户'''
          request = TOPRequest('taobao.item.sku.add')
          request['num_iid'] = num_iid
          request['properties'] = properties
          request['quantity'] = quantity
          request['price'] = price
          if outer_id!=None:
              request['outer_id'] = outer_id
          if item_price!=None:
              request['item_price'] = item_price
          if lang!=None:
              request['lang'] = lang
          self.create(self.execute(request, session)['sku'])
          return self
docs: taobao.item.sku.add 添加SKU
          
          新增一个sku到num_iid指定的商品中 传入的iid所对应的商品必须属于当前会话的用户