如何读取S3中所有子文件夹中的所有csv文件？

import os
import pandas as pd
from qcloud_cos import CosConfig
from qcloud_cos import CosS3Client

# 配置腾讯云 COS连接信息
secret_id = 'your_secret_id'
secret_key = 'your_secret_key'
region = 'your_region'
bucket = 'your_bucket'
token = None
config = CosConfig(Region=region, SecretId=secret_id, SecretKey=secret_key, Token=token)
client = CosS3Client(config)

# 递归遍历S3存储桶中的所有文件和文件夹
def traverse_folder(folder):
    response = client.list_objects(Bucket=bucket, Prefix=folder)
    contents = response.get('Contents', [])
    for content in contents:
        key = content['Key']
        if key.endswith('.csv'):
            # 读取csv文件内容
            response = client.get_object(Bucket=bucket, Key=key)
            csv_content = response['Body'].read()
            df = pd.read_csv(csv_content)
            # 在这里可以对csv文件进行处理或分析
            print(df.head())
        else:
            # 递归遍历子文件夹
            traverse_folder(key)

# 从根目录开始遍历
traverse_folder('')