四个python基础题目，求助，感谢

第一题和第二题：

def count(n):
    try:
        n = int(n)
    except ValueError:
        raise '请输入大于0的整数！'
    if n <= 0:
        raise '请输入大于0的整数！'
    else:
        result = 0
        for i in range(1,n+1):
            result += 2*i-1
    return result

print(count(input('请输入大于0的整数：')))

第三题：

def add_record():
    table = []
    with open('3_3.txt', mode='rt') as f:
        for i in f:
            table.append(i)
        table.append(
            '\n'+'url:https://www.google.com/,e-mail:maker@163.com,usernamfor:maker')
        ret = ''
        for i in table:
            ret += i
    with open('3_3.txt', mode='wt') as f:
        f.write(ret)


def display_record():
    dic = []
    with open('3_3.txt', mode='rt') as f:
        for i in f:
            temp = {}
            a = i.split(',')
            for i in a:
                b = i.split(':',1)
                temp[b[0]] = b[1]
            dic.append(temp)
    print(dic)

add_record()
display_record()

第四题：

def time_to_file(file_name):
    import time
    now = time.strftime('%Y年%m月%d日%H时%M分%S秒')
    with open(file_name,'at') as f:
        f.write(now+'\n')

time_to_file('time.txt')