先看看下面的几个方法：
参数：
target 是函数名字，需要调用的函数
args 函数需要的参数，以 tuple 的形式传入
用法：
multiprocessing.Process(group=None, target=None, name=None, args=(), kwargs={}, *, daemon=None)
写一个的例子：
from multiprocessing import Pool
import os,time
def pr(str):
print("The " + str + " is %s" %(os.getpid()))
time.sleep(1)
print("The " + str + " is close")
if __name__ == "__main__":
print('-------------------------------')
print("the current pid: "+ str(os.getpid()))
# 默认为自己电脑的核数
p = Pool(2)
for i in range(5):
p.apply_async(pr,args=('xdxd',))
p.close()
p.join()
print("----------close-----------------")
通过结果可以看出，是2个进程同时启动，同时启动的进程数与pool中设置的数量和自己电脑的核数有关
结果：
------------------------------- the current pid: 9562 The xdxd is 9563 The xdxd is 9564 The xdxd is close The xdxd is close The xdxd is 9563 The xdxd is 9564 The xdxd is close The xdxd is close The xdxd is 9563 The xdxd is close ----------close-----------------
