如何从ldap连接中获取Dns主机名？

import ldap3

# 建立与LDAP服务器的连接
server = ldap3.Server('ldap://ldap.example.com', port=389)
conn = ldap3.Connection(server, user='username', password='password')
conn.bind()

# 构建LDAP搜索请求
base_dn = 'dc=example,dc=com'
filter_str = '(objectClass=dnsNode)'
attributes = ['cn']
conn.search(base_dn, filter_str, attributes=attributes)

# 获取搜索结果中的DNS主机名
dns_hostnames = []
for entry in conn.entries:
    dns_hostnames.append(entry.cn.value)

# 打印DNS主机名
for hostname in dns_hostnames:
    print(hostname)