参考博客
https://blog.csdn.net/cunchi4221/article/details/107475684

测试案例1

website = "JournalDev.com"
def return_website():
    return website
print(f'My favorite website is {return_website()}')

结果如下：
# 测试案例2

website = "JournalDev.com"
def print_website():
    global website
    print(f'My favorite website is {website}')
 
    website = 'Wikipedia.com'
    print(f'My favorite website is {website}')
print_website()

测试案例3

结果如下

测试案例4（我想对函数调用的次数进行计数，我记得在C++里是很好实现的

pythotn的做法如下

cnt=-1 

def f():
    global cnt
    cnt=cnt+1
    
f()
print(cnt)

测试结果如下