如何在python curl Postfield中传递编码的亚马逊s3签名网址？

import pycurl

# 创建一个Curl对象
curl = pycurl.Curl()

# 设置请求的URL
curl.setopt(curl.URL, "https://example.com")

# 设置请求方法为POST
curl.setopt(curl.POST, 1)

# 设置POST字段，包括编码的亚马逊S3签名网址
post_data = [
    ("field1", "value1"),
    ("field2", "value2"),
    ("s3_signed_url", "编码的亚马逊S3签名网址")
]
curl.setopt(curl.POSTFIELDS, post_data)

# 执行请求
curl.perform()

# 关闭Curl对象
curl.close()