python - 如何从列表中删除额外的 ''

Question

我试图打开两个文本文件，读取它们，并将内容放在两个单独的临时文件中，以便稍后调用它们。我有以下两个问题:

为什么有这么多''在 test_questions 列表中的前两个字符串之后？

为什么用于填充 test_answers 列表的字符串被附加到 test_questions 列表中？

代码如下所示:

from os import read

# vars to hold questions and answers from question bank and answer bank in format ready for quiz iterations
test_questions = []
test_answers = []

# placing questions in temp list called test_questions
def read_quest():
    bank = open("test_question_bank.txt", "r+")
    bank.seek(0)
    file_read_q = bank.readlines()
    start = 0
    stop = 5
    for i in file_read_q:
        temp_q = "".join(file_read_q[start:stop])
        print(test_questions.append(temp_q))
        start += 5
        stop += 5
    bank.close()

# placing answers in temp list called test_answers
def read_answers():
    ans = open("test_correct_ans.txt", "r+")
    file_read_a = ans.readlines()
    ans.seek(0)
    for i in file_read_a:
        i = i.strip("\n")
        print(test_questions.append(i))
    ans.close()
 
# adding questions
def add_quest():
    bank = open("test_question_bank.txt", "a")
    correct_ans = open("test_correct_ans.txt", "a")
    prompt = input("Please write question: ")
    ansa = input("Write answer for choice a): ")
    ansb = input("Write answer for choice b): ")
    ansc = input("Write answer for choice c): ")
    correct_opt = input("Which option is the correct answer? ")
    temp_quest = prompt + "\n(a) " + ansa + "\n(b) " + ansb + "\n(c) " + ansc + "\n\n"
    temp_quest2 = "".join(temp_quest)
    print(bank.write(temp_quest2))
    print(correct_ans.write(correct_opt + "\n"))
    bank.close()
    correct_ans.close()

read_quest()
read_answers()
print(test_questions)
print(test_answers)
#add_quest()

输出如下所示:

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['Where is North?\n(a) s\n(b) e\n(c) n\n\n', 'Where is South?\n(a) s\n(b) e\n(c) n\n\n', '', '', '', '', '', '', '', '', 'c', 'a']
[]

test_question_bank.txt的内容看起来像这样:

Where is North?
(a) s
(b) e
(c) n

Where is South?
(a) s
(b) e
(c) n

我的内容 test_correct_answers.txt看起来像这样:

c
a

Answer 1

您的文件中有很多空行(可能在最后，您没有注意到它们)。您可以通过运行以下命令来清除数据以去除任何空行:

# For each question
# If it is not a blank line
# Add it to the new list
test_questions = [question for question in test_questions if question]