SIPClientlibraryforpython。

使用Python编写SIP客户端库，以便与SIP服务器通信。可以使用第三方库，如PJSIP或SIP.py，也可以使用Python内置的socket库和SIP协议的规范。

代码示例：

import socket

class SIPClient:
    def __init__(self, server_address, local_address):
        self.server_address = server_address
        self.local_address = local_address
        self.socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        self.socket.bind(local_address)

    def register(self, username, password):
        message = "REGISTER sip:{0} SIP/2.0\r\n".format(self.server_address)
        message += "Via: SIP/2.0/UDP {0}\r\n".format(self.local_address)
        message += "From: <sip:{0}@{1}>\r\n".format(username, self.server_address)
        message += "To: <sip:{0}@{1}>\r\n".format(username, self.server_address)
        message += "Call-ID: 1\r\n"
        message += "CSeq: 1 REGISTER\r\n"
        message += "Contact: <sip:{0}@{1}>\r\n".format(username, self.local_address)
        message += "Content-Length: 0\r\n\r\n"

        self.socket.sendto(bytes(message, "utf-8"), (self.server_address, 5060))
        response = self.socket.recvfrom(4096)
        if "401 Unauthorized" in str(response):
            message = message.replace("CSeq: 1 REGISTER\r\n", "CSeq: 2 REGISTER\r\n")
            message += "Authorization: Digest username=\"{0}\", realm=\"{1}\", nonce=\"{2}\", uri=\"sip:{3}\", response=\"{4}\"\r\n".format(username, self.server_address, "nonce", self.server_address, "response")
            self.socket.sendto(bytes(message, "utf-8"), (self.server_address, 5060))
            response = self.socket.recvfrom(4096)
        return response

这是一个简单的SIP客户端类，可以使用register方法向SIP服务器注册用户。要使用此类，只需实例化SIPClient类并传递服务器地址和本地地址，然后调用register方法并传递用户名和密码。该方法将向SIP服务器发送注册请求，并返回服务器的响应。