编写一个函数，计算一个字符串中大写字母，小写字母，数字，其他字符各有多少个，函数的返回值是以元组的形式

def String(string):
    big = ()
    small = ()
    num = ()
    other = ()
    for i in string:
        if i.isupper():
            big += (i, )
        elif i.islower():
            small += (i, )
        elif i.isnumeric():
            num += (i, )
        else:
            other += (i, )
    return (len(big), len(small), len(num), len(other))


a_str = "234FS4DG,J,Fvg4fd"
a_touple = String(a_str)
print(a_touple)