如何仅将某些值记录到CSV？

import csv

# 要记录的值
values = [
    {'name': 'John', 'age': 25, 'city': 'New York'},
    {'name': 'Alice', 'age': 30, 'city': 'London'},
    {'name': 'Bob', 'age': 35, 'city': 'Paris'}
]

# CSV文件路径和列头
csv_file = 'data.csv'
fieldnames = ['name', 'age', 'city']

# 写入CSV文件
with open(csv_file, 'a', newline='') as file:
    writer = csv.DictWriter(file, fieldnames=fieldnames)
    
    # 如果文件为空，写入列头
    if file.tell() == 0:
        writer.writeheader()
    
    # 逐行写入值
    for value in values:
        writer.writerow(value)