从外部文件打印行并使用函数

Question

我设置了一个从文件打印并设置变量的功能，以便我可以从文件中选择哪一行。我设置q1 = 0，做一个打印行[q1]的函数。然后我改变q1的值并再次执行该功能以打印行[q1]，但这次它是一个不同的行。但我得到＆＃34; IndexError：列表索引超出范围＆＃34;。它没有超出范围，因为如果我打印行[5]它可以工作，但如果我设置q1 = 5并打印行[q1]它不会？ 该功能第一次运行但不是第二次运行。 这是课程，所以我求助于

def qs(): # ask questions
    global q1
    global a1
    global a2
    global a3
    global a4
    line = questions.readlines()
    if difficulty == "easy":
        print(line[q1])
        easyanswers = line[a1], line[a2]
        print(easyanswers)
    elif difficulty == "medium":
        print(line[q1])
        mediumanswers = line[a1], line[a2], line[a3]
        print(mediumanswers)
    elif difficulty == "hard":
        print(line[q1])
        hardanswers = line[a1], line[a2], line[a3], line[a4]
        print(hardanswers)
    else:
        print("Invalid difficulty selection")
        q()
    answer = input("Answer: ")

def qnumber(): # does next question
    global question
    global q1
    global a1
    global a2
    global a3
    global a4

    if question == 1:
        question = question + 1
        qs()
        qnumber()
    elif 1 < question < 6:
        question = question + 1
        q1 = q1 + 5

question = 1 # track of question number
q1 = 0 # question line number
a1 = 1 # answer 1 line number
a2 = 2 # answer 2 line number
a3 = 3 # answer 3 line number
a4 = 4 # answer 4 line number

qnumber()