完整的单例模式

import time
import threading

class Singsing:

    lock = threading.Lock()
    instance = None

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

    def __new__(cls, *args, **kwargs):
        if cls.instance:
            return cls.instance

        with cls.lock:
            if cls.instance:
                return cls.instance
            time.sleep(0.1)
            cls.instance = object.__new__(cls)
            return cls.instance


def task():
    singer = Singsing('name')
    print(singer)

for i in range(10):
    t = threading.Thread(target=task)
    t.start()