線程的使用書寫示例：
（1）
import threading
import time

def run(str1):
    print("task:", str1)
    time.sleep(5)

for i in range (30):
    t1 = threading.Thread(target= run ,args=("abc",))
    t2 = threading.Thread(target= run ,args=("cdef",))

    t1.start()
    t2.start()

（2）

import threading
import time

def run(str1):
    print("task:", str1)
    time.sleep(5)
　　 print("task done :",str1)
start_time=time.time()
for i in range (300):
    t1 = threading.Thread(target= run ,args=("str_%s"%i,))
    t1.start()

print("cost:",time.time()-start_time)#cost: 0.03604459762573242

（3）

import  threading
import time
class MyThreading(threading.Thread ):
    def __init__(self,name):
        super(MyThreading,self).__init__()
        self.name = name
    def run(self): #必須要寫成run函數
        print("姓名：",self.name)
        time.sleep(5)
t1 = MyThreading("張三")
t2 = MyThreading("李四")
t1.start()
t2.start()

（4）

import  threading
import time
class MyThreading(threading.Thread ):
    def __init__(self,name,sleep_time):
        super(MyThreading,self).__init__()
        self.name = name
        self.sleep_time=sleep_time
    def run(self):
        print("姓名：",self.name)
        time.sleep(self.sleep_time)
        print("task done...",self.name)
t1 = MyThreading("張三",2)
t2 = MyThreading("李四",4)
t1.start()
t2.start()
t1.join()
print("main threading ......")

"""
result:
        姓名： 張三
        姓名： 李四
        task done... 張三
        main threading ......
        task done... 李四
"""

python - threading