class Borg:
    __shared_state = {}
    
    def __init__(self):
        self.__dict__ = self.__shared_state
        # 其他初始化代码

# 使用示例
b1 = Borg()
b1.x = 10

b2 = Borg()
print(b2.x)  # 输出: 10
b2.x = 20

print(b1.x)  # 输出: 20

class ChildBorg(Borg):
    __shared_state = {}
    
    def __init__(self):
        Borg.__init__(self)
        # 子类特定初始化

import threading

class ThreadSafeBorg(Borg):
    _lock = threading.Lock()
    
    def safe_update(self, key, value):
        with self._lock:
            setattr(self, key, value)

class InitOnceBorg(Borg):
    def __init__(self):
        if not hasattr(self, '_initialized'):
            # 初始化代码
            self._initialized = True

class NamespacedBorg:
    _namespaces = {}
    
    def __init__(self, namespace='default'):
        self._namespace = namespace
        if namespace not in self._namespaces:
            self._namespaces[namespace] = {}
        self.__dict__ = self._namespaces[namespace]