写一个和别人聊天，收发信息的代码

编写一个简单的文本聊天程序，我们可以使用Python的socket库来模拟一个TCP客户端和服务器的通信。这里是一个基础的服务器端代码示例：

import socket

# 创建一个服务器 socket
server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_address = ('localhost', 12345)  # 地址和端口
server_socket.bind(server_address)
server_socket.listen(1)

print(f"Server is running on {server_address[0]}:{server_address[1]}")

while True:
    # 接受连接
    connection, client_address = server_socket.accept()
    print(f"Accepted connection from: {client_address}")

    try:
        while True:
            # 接收客户端的消息
            received_message = connection.recv(1024).decode()
            if not received_message:
                break
            print(f"Received: {received_message}")

            # 发送回复
            response = "You said: " + received_message
            connection.sendall(response.encode())

    except Exception as e:
        print(f"Connection closed by client: {e}")
        break

    finally:
        # 关闭连接
        connection.close()

对于客户端，你可以创建一个新的socket，连接到指定的服务器地址，然后循环读取用户输入并发送给服务器，接收服务器的响应：

import socket

client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client_socket.connect(('localhost', 12345))

while True:
    user_input = input("Type your message and press enter: ")
    client_socket.sendall(user_input.encode())

    # 收到服务器响应
    server_response = client_socket.recv(1024).decode()
    print(f"Server responded: {server_response}")

client_socket.close()

这只是一个最基础的例子，实际应用中可能需要添加异常处理、身份验证等机制。