用pickle加载类的实例？

Question

I am trying to use pickle to load an instance, which I have previously saved.

My code currently goes like so:

with open ("Character.pkl", "rb") as f:
      self = pickle.load(f)

While I am still inside the class, I can then access different attributes of my character.

# Code
with open ("Character.pkl", "rb") as f:
      self = pickle.load(f)
print(self.damage)

# Output
--> 10

However, outside of the class, when I try to access this, it throws an Attribute Error.

For reference, here is all the code:

# Modules

# For managing the saved and loaded dictionaries
import json

# To obtain the ability to randomly choose between items of a list
import random

# To manage folders and files
import os

# To clear the terminal
import click

# To save and load instances
import _pickle as pickle
class character:



  # When this class is initiated...
  def create(self, first, last, gender, race, class_, background, morales, attitude, accountName, gameName):

    # Explain character creation instructions
    print("Welcome to the character creator!\n\nHere, you will create your character for the upcoming adventures.\n\nOn any question, type '0' for a random option.")
    input("\nPress enter to continue...\t")

    # Genders to be randomly selected from if that option is chosen
    genders = ["male", "female"]

    # A list of the inputted character features
    features = [first, last, gender, race, class_, background, morales, attitude]

    # If the gender is to be randomly selected
    if gender == str(0):

      # Update the gender section of features to the randomly selected gender
      features[2] = random.choice(genders)

    # List of feature types for refering to files
    features_str = [str(features[2])+"first", "last", "gender", "race", "class", "background", "morales", "attitude"]

    # Get to the right directory to get random information
    os.chdir("../../../Code Sections/Info/")

    # Check through each inputted feature
    for i in range (len(features_str)):

      # If random
      if features[i] == str(0):

        # Open the file refering to the feature
        with open ("randoms" + ".json", "r") as f:

          # Load the dictionary
          loaded_dict = json.load(f)

        # Choose a random feature from the dictionary
        features[i] = random.choice(loaded_dict.get(features_str[i]))

    # Capitalize the first letter of the gender after using it for file opening (so it can be displayed)
    features[2] = features[2].capitalize()

    # Get to the account info directory
    os.chdir("../../Accounts/Account - {}/Game Saves/{}".format(accountName, gameName))

    # Give the character its desired attributes
    self.first, self.last, self.gender, self.race, self.class_, self.background, self.morales, self.attitude = features
    self.fullname = "{} {}".format(self.first, self.last)
    self.alignment = "{} {}".format(self.attitude, self.morales)
    self.damage = "10"
    self.defence = "15"

    # A dictionary of all features
    self.features = {"First Name":self.first, "Surname":self.last, "Full Name":self.fullname, "Gender":self.gender, "Race":self.race, "Class":self.class_, "Background":self.background, "Attitude":self.attitude, "Morales":self.morales, "Alignment":self.alignment, "Damage":self.damage, "Defence":self.defence}

    # Create a formatted version of the character data to be stored
    with open ("Character Sheet.txt", "w+") as f:
      for i in range (len(self.features)):
        f.write("\n" + list((self.features).keys())[i] + ": " + list((self.features).values())[i])

    # Store the formatted file's contents as the character's info sheet
    with open ("Character Sheet.txt", "r") as f:
      self.character_sheet = "Your Character:\n" + f.read()

    # Remove the text file
    os.remove("Character Sheet.txt")

    # Save this instance
    with open ("Character.pkl", "wb") as f:
      pickle.dump(self, f, -1)



  def load(self, accountName, gameName):

    # Get to the account info directory
    os.chdir(gameName)

    with open ("Character.pkl", "rb") as f:
      self = pickle.load(f)

    print(self.features) # <-- This prints the attributes fine, without any error



  def __init__(self, packaged_info):

    called_for, account_info, game_info = packaged_info

    if called_for == "create":
      self.create(input("\nWhat is your character's first name?\n\nInput:\t"), input("\nWhat is your character's last name?\n\nInput:\t"), input("\nWhat is your character's gender?\n\nInput:\t").lower(), input("\nWhat is your character's race?\n\nInput:\t"), input("\nWhat is your character's class?\n\nInput:\t"), input("\nWhat is your character's background?\n\nInput:\t"), input("\nWhat are your character's morales? (Eg. Neutral)\n\nInput:\t"), input("\nWhat is your character's attitude towards society? (Eg. Lawful)\n\nInput:\t"), account_info.get("Account Name"), game_info.get("Game Name"))
    elif called_for == "load":
      self.load(account_info.get("Account Name"), game_info.get("Game Name"))




 # The order in which this file is run
def run(packaged_info):

  # Unpackage info
  account_info, game_info, called_from = packaged_info

  # Clear the terminal
  click.clear()

  # Make character with desired attributes
  user_character = Character([called_from, account_info, game_info])
  print(user_character.features) # <-- This throws the attribute error
  return [account_info, game_info, user_character]

Apologies in advance; I am very new to OOP (and python as a whole) so my code is likely not the best, nor my terminology. I also did some research before posting this, but couldn't find an answer (that I could understand), so apologies if this is a duplicate post.

If anyone could help me with this, it would be much appreciated.

Answer 1

I managed to fix my issue by returning pickle.load(f) and calling the load() method directly instead of through the init () method.

The updated code is below:

# Modules

# For managing the saved and loaded dictionaries
import json

# To obtain the ability to randomly choose between items of a list
import random

# To manage folders and files
import os

# To clear the terminal
import click

# To save and load instances
import _pickle as pickle

# For each character in-game
class Character:

  # When this class is initiated...
  def create(self, first, last, gender, race, class_, background, morales, attitude, accountName, gameName):

    # Explain character creation instructions
    print("Welcome to the character creator!\n\nHere, you will create your character for the upcoming adventures.\n\nOn any question, type '0' for a random option.")
    input("\nPress enter to continue...\t")

    # Genders to be randomly selected from if that option is chosen
    genders = ["male", "female"]

    # A list of the inputted character features
    features = [first, last, gender, race, class_, background, morales, attitude]

    # If the gender is to be randomly selected
    if gender == str(0):

      # Update the gender section of features to the randomly selected gender
      features[2] = random.choice(genders)

    # List of feature types for refering to files
    features_str = [str(features[2])+"first", "last", "gender", "race", "class", "background", "morales", "attitude"]

    # Get to the right directory to get random information
    os.chdir("../../../Code Sections/Info/")

    # Check through each inputted feature
    for i in range (len(features_str)):

      # If random
      if features[i] == str(0):

        # Open the file refering to the feature
        with open ("randoms" + ".json", "r") as f:

          # Load the dictionary
          loaded_dict = json.load(f)

        # Choose a random feature from the dictionary
        features[i] = random.choice(loaded_dict.get(features_str[i]))

    # Capitalize the first letter of the gender after using it for file opening (so it can be displayed)
    features[2] = features[2].capitalize()

    # Get to the account info directory
    os.chdir("../../Accounts/Account - {}/Game Saves/{}".format(accountName, gameName))

    # Give the character its desired attributes
    self.first, self.last, self.gender, self.race, self.class_, self.background, self.morales, self.attitude = features
    self.fullname = "{} {}".format(self.first, self.last)
    self.alignment = "{} {}".format(self.attitude, self.morales)
    self.damage = "10"
    self.defence = "15"

    # A dictionary of all features
    self.features = {"First Name":self.first, "Surname":self.last, "Full Name":self.fullname, "Gender":self.gender, "Race":self.race, "Class":self.class_, "Background":self.background, "Attitude":self.attitude, "Morales":self.morales, "Alignment":self.alignment, "Damage":self.damage, "Defence":self.defence}

    # Create a formatted version of the character data to be stored
    with open ("Character Sheet.txt", "w+") as f:
      for i in range (len(self.features)):
        f.write("\n" + list((self.features).keys())[i] + ": " + list((self.features).values())[i])

    # Store the formatted file's contents as the character's info sheet
    with open ("Character Sheet.txt", "r") as f:
      self.character_sheet = "Your Character:\n" + f.read()

    # Remove the text file
    os.remove("Character Sheet.txt")

    # Save this instance
    with open ("Character.pkl", "wb") as f:
      pickle.dump(self, f, -1)

  def load(self, accountName, gameName):

    # Get to the account info directory
    os.chdir(gameName)

    with open ("Character.pkl", "rb") as f:
      return pickle.load(f)

  def __init__(self, packaged_info):

    called_for, account_info, game_info = packaged_info

    if called_for == "create":
      self.create(input("\nWhat is your character's first name?\n\nInput:\t"), input("\nWhat is your character's last name?\n\nInput:\t"), input("\nWhat is your character's gender?\n\nInput:\t").lower(), input("\nWhat is your character's race?\n\nInput:\t"), input("\nWhat is your character's class?\n\nInput:\t"), input("\nWhat is your character's background?\n\nInput:\t"), input("\nWhat are your character's morales? (Eg. Neutral)\n\nInput:\t"), input("\nWhat is your character's attitude towards society? (Eg. Lawful)\n\nInput:\t"), account_info.get("Account Name"), game_info.get("Game Name"))

 # The order in which this file is run
def run(packaged_info):

  # Unpackage info
  account_info, game_info, called_from = packaged_info

  # Clear the terminal
  click.clear()

  # Make character with desired attributes
  if called_from == "create":
    user_character = Character([called_from, account_info, game_info])
  elif called_from == "load":
    user_character = Character([called_from, account_info, game_info]).load(account_info.get("Account Name"), game_info.get("Game Name"))
  return [account_info, game_info, user_character]