python写函数，计算传入字符串中【数字】、【字母】、【空格] 以及 【其他】的个数

dic = {
    'number': 0,
    'letter': 0,
    'space': 0,
    'other': 0
}
def hao(info):
    if type(info) == str:
        for i in info:
            if i.isdigit():
                dic['number'] += 1
            elif i.isalpha():
                dic['letter'] += 1
            elif i.isspace():
                dic['space'] += 1
            else:
                dic['other'] += 1
    else:
        print('请输入字符串')
        exit()
    print(dic)
hao('123123==    ')