TypeError：“ int”對象在Python中不可調用

Question

python noob的一點，我需要在我的代碼中添加一個正則表達式，但無法使其正常工作：/我已經在Google上搜索了錯誤消息，並試圖找出問題所在，但是沒有運氣，所以我想出了下一個最好的方法要做的就是直接問。 這是到目前為止的代碼：

# allows us to access a random 'key' in the dictionary
import random
import re

# Contains the question and it's correct answer
my_dict =   {
            "A form of Protectionism that imposes a tax on imports" : "tariff",
            "....is quantity of a good or service that consumers are willing and able to     buy at a given price in a given time period" : "Demand", 
            "....is the quantity of a good or service that a producer is willing and able   to supply onto the market at a given price in a given time period" : "Supply",
            "By using ..... businesses can bring down their average costs by producing on a larger scale" : "Economies of scale",
            "The cost of the next best alternative" : "Opportunity Cost",
            ".... is the transfer of assets from the public (government) sector to the private sector." : "Privatisation"
        }


# welcome message
print("Economics Revision App")
print("=======================")



# the quiz will end when this variable becomes 'False'
playing = True


# While the game is running
while playing == True:

    # set the score to 0
    score = 0

    # gets the number of questions the player wants to answer
    num = int(input("\nHow many questions would you like: "))
    num = re.match("r\d[0-9]{2}$", num())
    if match:
        print ('foo')

    # loop the correct number of times
    for i in range(num):

        # the question is one of the dictionary keys, picked at random
        question = (random.choice( list(my_dict.keys())))
        # the answer is the string mapped to the question key
        answer = my_dict[question]

        # print the question, along with the question number
        print("\nQuestion " + str(i+1) )
        print(question  + "?")

        # get the user's answer attempt
        guess = input("> ")

        # if their guess is the same as the answer
        if guess.lower() == answer.lower():
            # add 1 to the score and print a message
            print("Correct!")
            score += 1
        else:
            print("Incorrect guess again!")

    # after the quiz, print their final score  
    print("\nYour final score was " + str(score))

    # store the user's input...
    again = input("Enter any key to play again, or 'q' to quit.")

    #... and quit if they types 'q'
    if again.lower() == 'q':
        playing = False

我在問題中苦苦掙扎的代碼

Answer 1

num = re.match("r\\d[0-9]{2}$", num())

num只是一個整數，因此num()無效。

應該類似於match = re.match("r\\d[0-9]{2}$", str(num))

1）應該match嗎？

2） re正在對str ，因此傳遞的參數應為str(num)

然后，代碼也應該很好玩。 :)