python辞書の値を更新する

Question

だから、私はPython辞書を追加して更新しています。現在はかなり醜いように見え、読みにくいですが、同じことをやっているより良い方法がありますか？

 if not transaction_id in self.transaction_log: 
      self.transaction_log[transaction_id] = { 
       'gross_total': 0, 
       'net_total': 0, 
       'qty_total': 0, 
       'tax_total': 0 
      } 
      self.transaction_log[transaction_id]['products'] = {} 


     # create a list of dics to be reused in 
     # other class methods 
     self.transaction_log[transaction_id].update({ 
      'transaction_id': transaction_id, 
      'transaction_time': transaction_datetime, 
      'location_id': location_id, 
      'till_id': till_id, 
      'employee_id': employee_id, 

     }) 

     self.transaction_log[transaction_id]['products'][product_id] = { 
      'gross': gross, 
      'net': net, 
      'tax': tax, 
      'qty': qty 
     } 

     self.transaction_log[transaction_id]['gross_total'] += gross 
     self.transaction_log[transaction_id]['net_total'] += net 
     self.transaction_log[transaction_id]['qty_total'] += tax 
     self.transaction_log[transaction_id]['tax_total'] += qty 

Answer 1

これはcodereview.stackexchange.comのために、より適切であるかもしれない：

transaction = self.transaction_log.setdefault(transaction_id, { 'products': {} }) 

# create a list of dics to be reused in 
# other class methods 
transaction.update({ 
    'gross_total': transaction.get('gross_total', 0) + gross, 
    'net_total': transaction.get('net_total', 0) + net, 
    'qty_total': transaction.get('qty_total', 0) + qty, 
    'tax_total': transaction.get('tax_total', 0) + tax, 
    'transaction_id': transaction_id, 
    'transaction_time': transaction_datetime, 
    'location_id': location_id, 
    'till_id': till_id, 
    'employee_id': employee_id 
}) 
transaction['products'].update({ 
    product_id: { 
     'gross': gross, 
     'net': net, 
     'tax': tax, 
     'qty': qty 
    } 
}) 

また、それはあなたがqtyと