Python：将逗号分隔的数据写入 .csv 文件的问题

目标：

1. 从 a 中读取股票价格数据.csv file
2. 重新采样
3. 最后将输出打印到一个新的.csv file，其中所有列都以逗号分隔。

问题：

目前，该程序可以 1) 读取数据并 2) 对其重新采样，但是在打印到输出.csv时没有逗号分隔符。此外，列标题不会打印在相同的第一行。

输入数据样本：

*感兴趣的列：第一列（日期/时间）、第二列（买入价）和第四列（卖出价）。

20210602 22:02:00,3.07,50,3.086,50
20210602 22:03:00,3.07,50,3.087,50
20210602 22:04:00,3.071,50,3.087,50
20210602 22:04:00,3.071,50,3.088,50
20210602 22:05:00,3.07,50,3.088,50
20210602 22:05:00,3.07,50,3.087,50
20210602 22:06:00,3.071,50,3.087,50

电流输出：

                     open    high    low      close
Date_time
2021-06-02 22:02:00  3.0790  3.0790  3.0780  3.0780
2021-06-02 22:03:00  3.0785  3.0785  3.0785  3.0785
2021-06-02 22:04:00  3.0790  3.0795  3.0790  3.0795
2021-06-02 22:05:00  3.0790  3.0790  3.0785  3.0785
2021-06-02 22:06:00  3.0790  3.0790  3.0790  3.0790

预期输出：

Date_time,open,high,low,close
2021-06-02 22:02:00,3.0790,3.0790,3.0780,3.0780
2021-06-02 22:03:00,3.0785,3.0785,3.0785,3.0785
2021-06-02 22:04:00,3.0790,3.0795,3.0790,3.0795
2021-06-02 22:05:00,3.0790,3.0790,3.0785,3.0785
2021-06-02 22:06:00,3.0790,3.0790,3.0790,3.0790

程序尝试：

import pandas as pd
import sys

data_frame = pd.read_csv('03-06-21-xngusd.csv',
                         names=['Date_time', 'Bid', 'Bid qty',
                                  'Ask', 'Ask qty'],
                         index_col=0, parse_dates=True)
data_frame.head()

# Resample the data into 1 minute increments
data_ask = data_frame['Ask'].resample('1MIN').ohlc()
data_bid = data_frame['Bid'].resample('1MIN').ohlc()
data_mid = (data_ask + data_bid) / 2

data_mid.head()

# Print the new resample data to a .csv file
original_stdout = sys.stdout # Save reference to original standard output
with open('filename.csv', 'w') as f:
    sys.stdout = f
    print(data_mid)
    sys.stdout = original_stdout

还尝试了以下代码，它只打印了第一行并且还错过了显示输出的第一列标题open, high, low, close：

with open('filename.csv', 'w') as writeFile:
    writer = csv.writer(writeFile, delimiter=',')
    writer.writerow(data_mid)

Q1。如何修改程序以确保输出列是comma delimited？

Q2。如何将列标题打印到文件顶部的同一行？