将嵌套的默认字典写入csv

import csv

data = {
    'name': 'John',
    'age': 30,
    'address': {
        'street': '123 Main St',
        'city': 'New York',
        'state': 'NY'
    }
}

def flatten_dict(d, parent_key='', sep='.'):
    items = []
    for k, v in d.items():
        new_key = f"{parent_key}{sep}{k}" if parent_key else k
        if isinstance(v, dict):
            items.extend(flatten_dict(v, new_key, sep=sep).items())
        else:
            items.append((new_key, v))
    return dict(items)

# 将嵌套的默认字典扁平化
flattened_data = flatten_dict(data)

# 获取所有键的集合
keys = flattened_data.keys()

# 创建CSV文件并写入数据
with open('data.csv', 'w', newline='') as csvfile:
    writer = csv.DictWriter(csvfile, fieldnames=keys)
    writer.writeheader()
    writer.writerow(flattened_data)