AssertionError: Thread.__init__() not called

在使用thread的时候，定义如下类：

class newThread(threading.Thread):
    def __init__(self, threadID, name, counter):
        threading.Thread.__init__(self)
        self.threadID = threadID
        self.name = name
        self.counter = counter

注意：

"If the subclass overrides the constructor, it must make sure to invoke the base class constructor (Thread.__init__()) before doing
anything else to the thread."

也就是说子类的__init__()方法调用父类的__init__方法，一定要在第一行调用。否则会出标题上的错误！