Pythonで単一のdict要素を置き換える

Question

私は文字列のリストを持つオブジェクトのdictをすべて指定した文字列のリストから入力しようとしています。問題は、dictの1つの要素を置き換えたい場合、すべての要素が変更されることです。

Personクラス：

class Person: 

    messages = [] 

    def __init__(self, p): 
     self.name = p 

    def add_message(self, m_text): 
     self.messages.append(m_text) 

メインコード：

chat_messages_list = ["Eva: Eva's first text", "Eva: Eva's second text", "Eva: Eva's third text", 
         "Harry: Harry's first text", "Harry: Harry's second text", "Harry: Harry's third text", 
         "Ellis: Ellis' first text", "Ellis: Ellis' second text", "Ellis: Ellis' third text"] 
dict_persons = {} 

for element in chat_messages_list: 

    split_messages = element.split(": ") 
    name = split_messages[0] 
    message_text = split_messages[1] 

    # Create Person in list if not already exists 
    if name not in dict_persons: 
     dict_persons[name] = Person(name) 

    person = dict_persons[name] 

    # THE PROBLEM: Following line will add message_text to EVERY Person in dict_persons 
    person.add_message(message_text) 

for key, value in dict_persons.items(): 
    print("{0}: {1}".format(key, value.messages)) 

期待される結果：

Eva: ["Eva's first text", "Eva's second text", "Eva's third text"] 
Harry: ["Harry's first text", "Harry's second text", "Harry's third text"] 
Ellis: ["Ellis' first text", "Ellis' second text", "Ellis' third text"] 

実際の結果：

Eva: ["Eva's first text", "Eva's second text", "Eva's third text", "Harry's first text", "Harry's second text", "Harry's third text", "Ellis' first text", "Ellis' second text", "Ellis' third text"] 
Ellis: ["Eva's first text", "Eva's second text", "Eva's third text", "Harry's first text", "Harry's second text", "Harry's third text", "Ellis' first text", "Ellis' second text", "Ellis' third text"] 
Harry: ["Eva's first text", "Eva's second text", "Eva's third text", "Harry's first text", "Harry's second text", "Harry's third text", "Ellis' first text", "Ellis' second text", "Ellis' third text"] 

Wyは、必要なものだけでなく、dictのすべてのオブジェクトに追加される文字列ですか？

Answer 1

__init__のフィールドをPersonのself.messages = []に初期化してインスタンスフィールドにします。
今はクラスレベルのフィールドなので、すべてのインスタンスが同じリストを共有します。

Answer 2

はあなたのinitでmessages = []を入れてみてください：これは私のために働いた

class Person: 

    def __init__(self, p): 
     self.name = p 
     self.messages = [] 

    def add_message(self, m_text): 
     self.messages.append(m_text) 

を！