为什么我不能将我的 python 类保存到 JSON 文件中？

Question

I'm making an expense tracker. I've created an Account class, that registers a specific budget. All the accounts are saved in a Budgets list. Then I try to save the Budgets list into a json file using the save function, which returns an error. This is kinda obvious, but I can't think of any efficient alternative. Any solution? PD: I deleted all the structure not related with the problem, because it already works, and it doesn't let me send all the code. Sorry if something seems out of context.

def initialize(filename):
   """
   Adjusts the starting parameters.
   """

   budgets = []

   try: 
   # Checks if the file exists, and executes the apropiate code
   # according to the situation.
       with open(filename, 'r') as f_obj: 
           budgets = json.load(f_obj) 
           # Loads the info from older sessions 
           # into the list.

   except FileNotFoundError: #If the file doesn't exist, we create it.
       print("Seems you are the first one here!")

       return budgets




class Account:
   """

   Simulates a budget with custom percentatges for each area of spending

   """
   def __init__(self, name, cash, percent):
       self.name = name
       self.cash = int(cash)
       self.percent = percent
       self.budget = {}

       for key, value in self.percent.items():
           self.budget[key] = self.cash * value / 100


def save(filename, budgets):
   """Saves the changes made into the accounts"""

   with open(filename, 'w') as f_obj: 
       json.dump(budgets, f_obj)

def main():
   """Executes the main program"""

   filename = "budgets.json"

   budgets = initialize(filename)

   while True:
       a = input("\nSelect the desired operation (h for help): ")

       if a == 'help':
           help()


       elif a == 'save':
           save(filename, budgets)
           print('account saved succesfully')

       elif a == 'exit':
           break

       else:
           print("ERROR: The input is not an operation\n")

Answer 1

I am really not sure about my solution, but!!! If I remember correctly, you can only serialize dictionaries in json, so maybe try this out:

def save(filename, budgets):
   """Saves the changes made into the accounts"""

   with open(filename, 'w') as f_obj: 
       budgets2 = [budget.__dict__ for budget in budgets]
       json.dump(budgets2, f_obj)