python如何重写父类的方法

import threading

import time

def catch_fish():

Pass

def one_thread():  

 start_time = time.time()   

for i in range(1, 1001):      

 catch_fish()   

end_time = time.time()   

print("单线程测试 耗时 === %s" % str(end_time - start_time))

def muti_thread():  

 start_time = time.time()  

 for i in range(1, 1001):       

threading.Thread(target=catch_fish()).start()   

end_time = time.time()   

print("多线程测试 耗时 === %s" % str(end_time - start_time))

if __name__ == '__main__':   

# 单线程   

threading.Thread(one_thread()).start()   

# 多线程   

muti_thread()