以打电话为理解方式进行TCP的通信。
Server端代码：
import socket
phone = socket.socket(socket.AF_INET, socket.SOCK_STREAM)     #购买电话卡，AF_INET服务器之间网络通信，socket.SOCK_STREAM，流式协议，就是TCP协议
phone.bind(('127.0.0.1', 8080))                               #选择电话号码，绑定IP地址
phone.listen(5)                                               #开机，监控5个请求，最多能进入6个，第7个会报错
conn, addr = phone.accept()                                   #等待接听电话，阻塞状态，获取IP和端口
print(conn, addr)                                             #打印IP和端口
client_data = conn.recv(1024)                                 #交流过程
print(client_data)                                            #打印接收到的数据
conn.send(client_data.upper())                                #接收到的英文字母变成大写并回传数据
conn.close()
phone.close()

Client端代码：
import socket
phone = socket.socket()
phone.connect(('127.0.0.1', 8080))
msg = input('>>>').strip()
phone.send(msg.encode('utf-8'))
server_data = phone.recv(1024)                                #限制最大接收字节
print(server_data)
phone.close()

先运行Server端，再运行Client端，输入：Others laugh at me for being mad. I laugh at others for not being able to see through.
------------------------------------Client端运行结果---------------------------------------
>>>Others laugh at me for being mad. I laugh at others for not being able to see through.
b'OTHERS LAUGH AT ME FOR BEING MAD. I LAUGH AT OTHERS FOR NOT BEING ABLE TO SEE THROUGH.'
------------------------------------------------------------------------------------------

------------------------------------Server端运行结果----------------------------------------
<socket.socket fd=244, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('127.0.0.1', 8080), raddr=('127.0.0.1', 64096)> ('127.0.0.1', 64096)
b'Others laugh at me for being mad. I laugh at others for not being able to see through.'
-------------------------------------------------------------------------------------------

Server端代码：
import socket
phone = socket.socket(socket.AF_INET, socket.SOCK_STREAM)  #使用TCP协议创建网络通信
phone.bind(('127.0.0.1', 8080))                            #绑定IP地址和端口
phone.listen(5)                                            #设置最大连接数，但是同一时间只能处理一个请求while 1:                                                   #使服务端能够一直接受数据
    conn, addr = phone.accept()                            #获取连接到服务器的IP和端口
    try:
        client_data = conn.recv(1024)                      #接收1024字节的数据
        print(client_data)                                 #打印数据（数字为bytes类型）
        conn.send(client_data + b'-yes-')                  #源数据加上-yes-并返回给客户端
    except Exception:
        break
conn.close()
phone.close()


Client端代码：
import socket
phone = socket.socket()
phone.connect(('127.0.0.1', 8080))

while 1:
    msg = input('>>>').strip()                             #可输入要传输的字符
    if msg.upper() == 'Q':                                 #如果输出q则退出
        break
    elif not msg:                                          #如果msg接到到的内容为空，则结束本次循环
        continue
    phone.send(msg.encode('utf-8'))                        #使用utf-8的编码进行发送数据
    server_data = phone.recv(1024)                         #最多只能接受1024字节，只问题会产生粘包
    print(server_data.decode('utf-8'))                     #打印解码后的数据
phone.close()

------------------------------------Client端运行结果---------------------------------------
>>>laugh                                                   #输入要传到S端的内容
laugh-yes-                                                 #打印出来的是S端返回的内容
>>>crazy
crazy-yes-
>>>q

Process finished with exit code 0
-------------------------------------------------------------------------------------------

------------------------------------Server端运行结果----------------------------------------

b'laugh'                                                   #收到C端发送来的内容
b'crazy' 

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