利用python的标准库hashlib 的md5()生成唯一的id

import hashlib
import time

def generate_md5():
    m = hashlib.md5()
    m.update(bytes(str(time.perf_counter()),encoding='utf8')) #perf_counter() 可以精确到纳秒级别（保证不会重名）
    return m.hexdigest()

class School():
    def __init__(self,s_id,name,addr):
        self.id = s_id
        self.name = name
        self.addr = addr
    def printInfo(self):
        print("学校id：{}".format(self.id))

class Course():
    def __init__(self,c_id,name,addr):
        self.id = c_id
        self.name = name
        self.addr = addr
    def printInfo(self):
        print("课程id：{}".format(self.id))

if __name__ =="__main__":
 27     school = School(generate_md5(),"KAIYUAN","ShangHai")
    course = Course(generate_md5(),"Python","Beijing")

    school.printInfo()
    course.printInfo()

注：可以作为文件名后缀。