I try to run example from : https://docs.python.org/3/library/socketserver.html#socketserver-tcpserver-example in my laptop but it didn't work.

Server :

import socketserverclass MyTCPHandler(socketserver.BaseRequestHandler):"""The request handler class for our server.It is instantiated once per connection to the server, and mustoverride the handle() method to implement communication to theclient."""def handle(self):# self.request is the TCP socket connected to the clientself.data = self.request.recv(1024).strip()print("{} wrote:".format(self.client_address[0]))print(self.data)# just send back the same data, but upper-casedself.request.sendall(self.data.upper())if __name__ == "__main__":HOST, PORT = "localhost", 9999# Create the server, binding to localhost on port 9999with socketserver.TCPServer((HOST, PORT), MyTCPHandler) as server:# Activate the server; this will keep running until you# interrupt the program with Ctrl-Cserver.serve_forever()

Client :

import socket
import sysHOST, PORT = "localhost", 9999
data = " ".join(sys.argv[1:])# Create a socket (SOCK_STREAM means a TCP socket)
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:# Connect to server and send datasock.connect((HOST, PORT))sock.sendall(bytes(data + "\n", "utf-8"))# Receive data from the server and shut downreceived = str(sock.recv(1024), "utf-8")print("Sent:     {}".format(data))
print("Received: {}".format(received))

This error is showing on both client and server site :

Traceback (most recent call last):File "C:\Users\Win7_Lab\Desktop\testcl.py", line 8, in <module>with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
AttributeError: __exit__
[Finished in 0.1s with exit code 1]
[shell_cmd: python -u "C:\Users\Win7_Lab\Desktop\testcl.py"]
[dir: C:\Users\Win7_Lab\Desktop]
[path: C:\Python27\;C:\Python27\Scripts;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\]

It looks like the example you're trying to run is for Python 3, while the version you're running is Python 2.7. In particular, support for using a context manager (i.e. with socket.socket()) was added in Python 3.2.

Changed in version 3.2: Support for the context manager protocol wasadded. Exiting the context manager is equivalent to calling close().

If you don't want to upgrade, you should be able to modify your code by removing the with statements and calling close(), perhaps using a try statement:

try:server = socketserver.TCPServer((HOST, PORT), MyTCPHandler)# Activate the server; this will keep running until you# interrupt the program with Ctrl-Cserver.serve_forever()
except:pass
finally:server.close()

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