为什么print语句运行的次数是实际运行次数的两倍？ [关闭]

This is the question: The guest_list function reads in a list of tuples with the name, age, and profession of each party guest, and prints the sentence "Guest is X years old and works as __." for each one. For example, guest_list(('Ken', 30, "Chef"), ("Pat", 35, 'Lawyer'), ('Amanda', 25, "Engineer")) should print out: Ken is 30 years old and works as Chef. Pat is 35 years old and works as Lawyer. Amanda is 25 years old and works as Engineer. Fill in the gaps in this function to do that.

这是我的代码：

def guest_list(guests):
    for i,x in enumerate(guests):
        print("{} is {} years old and works as {}".format(x[0],x[1],x[2]))

guest_list([('Ken', 30, "Chef"), ("Pat", 35, 'Lawyer'), ('Amanda', 25, "Engineer")])

O / P是这样的：/

Ken is 30 years old and works as Chef
Pat is 35 years old and works as Lawyer
Amanda is 25 years old and works as Engineer
Ken is 30 years old and works as Chef
Pat is 35 years old and works as Lawyer
Amanda is 25 years old and works as Engineer
None