寻找将对象放入“列表对象”的OOP Pythonic方法，而不是仅使用[list]

Question

由于某种原因，我无法概念化如何使用Checkbook.class对象而不是“ ledger [list]”。什么是实现本准则目标的最佳实践方法？（是的，我也有其他“新手”问题，但是我很乐意得到一些建议。）

import sys

import time

transNum=0

ledger = []

debitInput=['Check Number: ', 'Transaction Date: ',

            'Payee: ', 'Amount: ', 'Memo (or Enter to skip): ']

creditInput=['Check Number: ', 'Transaction Date: ',

            'Source: ', 'Amount: ', 'Memo (or Enter to skip): ']

# a Payee is a persistent record/lookup of current, past and new payees

class Payee:

    pass

# a Source is a persistent record/lookup of current, past and new sources

class Source:

    pass

# a Checkbook is a collection of Transaction objects upon which queries may be performed

class Checkbook:

    def __init__(self, newTrans):

        pass

# a Transaction is a collection of Debit and Credit objects

class Transaction:

    def __init__(self, chkNum, transDate, thirdParty, amount, memo=''):

        self.chkNum = chkNum

        self.transDate = transDate

        self.memo=memo

        self.thirdParty=thirdParty

        self.amount=amount

        self.transNum = transNum

class Debit(Transaction):

    def __init__(self, *args):

        Transaction.__init__(self, *args)

        self.payee=self.thirdParty

        del self.thirdParty

        self.amount=int(self.amount)*-1

class Credit(Transaction):

    def __init__(self, *args):

        Transaction.__init__(self, *args)

        self.source=self.thirdParty

        del self.thirdParty

        self.amount=int(self.amount)

while True:

    transact = []

    transNum += 1

    choice=input('Posting debit [d], credit [c] or [x] to exit: ')

    if choice == 'x': break

    elif choice == 'd':

        for field in debitInput:

            field = input(field)

            transact.append(field)

        trans = Debit(transact[0], transact[1], transact[2], transact[3], transact[4])

        ledger.append(trans)

Answer 1

class Checkbook:    def __init__(self):        self.transactions = []    # Checkbook is just a wrapper around a list    def __getitem__(self, index): # implementing [x]        return self.transactions[index]    def __setitem__(self, index, transaction): #implementing [x] = i        self.transactions[index] = transaction    def append(self, transaction): # implementing .append(x)        self.transactions.append(transaction)    def extend(self, transaction_list): # implementing .extend([x,y,z])        self.transactions.extend(transaction_list)    # and so on for every method which you want to support或者，您可以继承list。这是做作业吗？在Python中分配它是很愚蠢的。您永远不会真正想要继承list。在大学里，我有一个更好的练习，在该练习中，我必须重新std::vector使用模板，动态数组（带有malloc()）和运算符重载……，这真有趣！该std::map演习是更好:)