如何使用字符串刪除python中的括號？

Question

我有這個程序：

import sys
students = []
grades = []

while True:
    student = input ("Enter a name: ").replace(" ","")
    if  student.isalpha() == True and student != "0":
        while True:
            grade = input("Enter a grade: ").replace(" ","")
            if grade == "0" or grade == 0:
                print ("\n")
                print ("A zero is entered.")
                sys.exit(0)
            if grade.isdigit()== True: 
                grade = int(grade)
                if grade >= 1 and grade <= 10:
                    if student in students:
                        index = students.index(student)
                        grades[index].append(grade)
                        break
                    else:
                        students.append(student)
                        grades.append([grade])
                        break
                else:
                    print("Invalid grade.")
    elif student == "0": 
        print("A zero is entered.")
        break
    else:
        print ("Invalid name.")
for i in range(0,len(students)): 
    print("NAME: ", students[i])
    print("GRADE: ", grades[i])
    print("AVERAGE: ", round(sum(grades[i])/len(grades[i]),1), "\n")

例如，當程序打印它們時，我需要使數字之間的[]消失。

輸入數字時，如下所示：

Enter a name: Jack
Enter a grade: 8
Enter a name: Jack
Enter a grade: 9
Enter a name: Jack
Enter a grade: 7
Enter a name: 0
A zero is entered.

它打印如下：

NAME:  Jack
GRADE:  [8, 9, 7]
AVERAGE:  8.0 

但是我需要程序像這樣打印：

 NAME:  Jack
 GRADE:  8, 9, 7
 AVERAGE:  8.0 

成績應無括號。 我想我需要使用字符串之類的東西，有人知道嗎？

Answer 1

strip可讓您從開頭和結尾刪除指定的字符。

str(grades[i]).strip('[]')

Answer 2

如果grades是整數列表的列表：

print(', '.join(str(i) for i in grades[g])) # where g sublist index

Answer 3

第一：

>>> grades = [[1,2,3],[4,5,6]]

現在您有幾種選擇：

>>> print("GRADE:", *grades[0])
GRADE: 1 2 3

要么：

>>> print("GRADE:", ', '.join(map(str, grades[0])))
GRADE: 1, 2, 3

或者，在腳本或代碼塊中：

print("GRADE: ", end='')
print(*grades[0], sep=', ')

以上結果：

GRADE: 1, 2, 3

根據需要將[0]替換為[i] 。