TypeError:只能将元组(不是"str")连接到元组错误

Question

只是试图让一个元组添加到我的主要编程.无论如何这是我的代码 -

print"I have a few things to finish my exam, but i might need more"
exam=("Brain","Computer","python")
print "The stuff i have are:"
for stuff in exam:
    print stuff
print"I still need my previous assignments!"
extra=("Assignments")
exam += extra
for stuff in exam:
    print stuff

---

我一直得到的只能连接元组错误.任何人都有一个线索我的问题/如何解决它？非常感激.

Answer 1

那是因为根据python doc

元组由逗号运算符构造(不在方括号内),带或不带括号,但空元组必须有括号括起来,例如a,b,c或().单个项元组必须有一个尾随逗号,例如(d,).

所以,如果你对你的代码这样做,它必须工作

extra = "Assignments", 

要么

extra = ("Assignments",)