各位大神，这道题可以看看嘛？CSV文件咋弄呀

import csv
import os
import random
from matplotlib import markers
import matplotlib.pyplot as plt
import pandas as pd

if not os.path.exists("data.csv"):
    #创建存储csv文件存储数据
    file = open('data.csv', "w", encoding="utf-8-sig",newline='')
    csv_head = csv.writer(file)
    #表头
    header = ['date','price']
    csv_head.writerow(header)
    file.close()
    

for i in range(12):
    base = 1.5
    base_add = base + 0.003 * i
    r = 0
    if i != 0:
        r = random.random() * 0.03 - 0.01
        print(r)
    price = base_add + r
    with open('data.csv', 'a+', encoding='utf-8-sig') as f:
                f.write(str(i+1) + ',' + str(price) + '\n')

df = pd.read_csv('data.csv', encoding='utf-8-sig',usecols=["date", "price"])

date = df['date'].values + 1
price = df['price'].values * 10000

plt.plot(date,price,marker='o', color='r')
plt.xlabel('月份')
plt.ylabel('成交均价（元）')
plt.title('某市二手房屋历史均价走势图')
plt.legend()
plt.rcParams['font.sans-serif'] = ['SimSun']
plt.show()