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I would like to ask about your opinion about my code. The idea is simple: I designed my own protocol, where client asks server about the image, and the server sends the image, following the below steps (this is the actual protocol I wanted to implement):

CLIENT SERVER
 GET\r\n 
 ----------------------------------->
 OK\r\n
 <----------------------------------- 
 GET_SIZE\r\n
 ----------------------------------->
 SIZE 1024\r\n
 <-----------------------------------
 GET_IMG\r\n
 ----------------------------------->
 IMG_DATA an when image sending is over, EOIMG\r\n 
 <-----------------------------------
 DONE\r\n
 ----------------------------------->
 server disconnects the client 

I improved the code as suggested by @TobErnack, but still, would like to know your opinion of my improvements. Here's the link to the original question and code: Network protocol using TCP, sending images through sockets

Everything works (it seems so) but I would like to ask, what else I could possibly improve here.

1. Does the implementation reflects in 100% what I wanted to achieve in my protocol flow?
2. Are the steps implemented as I wanted them to be in my protocol?

client.py

#!/usr/bin/env python
import socket
import sys
HOST = '127.0.0.1'
PORT = 6666
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_address = (HOST, PORT)
sock.connect(server_address)
fname = 'fromserver.png'
def recvall(sock, msgLen):
 msg = ""
 bytesRcvd = 0
 while bytesRcvd < msgLen:
 chunk = sock.recv(msgLen - bytesRcvd)
 if chunk == "": break
 bytesRcvd += len(chunk)
 msg += chunk
 if "\r\n" in msg: break
 return msg
try:
 sock.sendall("GET\r\n")
 data = recvall(sock, 4096)
 if data:
 txt = data.strip()
 print '--%s--' % txt
 if txt == 'OK':
 sock.sendall("GET_SIZE\r\n")
 data = recvall(sock, 4096)
 if data:
 txt = data.strip()
 print '--%s--' % txt
 if txt.startswith('SIZE'):
 tmp = txt.split()
 size = int(tmp[1])
 print '--%s--' % size
 sock.sendall("GET_IMG\r\n")
 myfile = open(fname, 'wb')
 amount_received = 0
 while amount_received < size:
 data = recvall(sock, 4096)
 if not data:
 break
 amount_received += len(data)
 print amount_received
 txt = data.strip('\r\n')
 if 'EOIMG' in str(txt):
 print 'Image received successfully'
 myfile.write(data)
 myfile.close()
 sock.sendall("DONE\r\n")
 else:
 myfile.write(data)
finally:
 sock.close()

server.py

# !/usr/bin/env python
import random
import socket, select
from time import gmtime, strftime
image = 'tux.png'
HOST = '127.0.0.1'
PORT = 6666
connected_clients_sockets = []
server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
server_socket.bind((HOST, PORT))
server_socket.listen(10)
connected_clients_sockets.append(server_socket)
def recvall(sock, msgLen):
 msg = ""
 bytesRcvd = 0
 while bytesRcvd < msgLen:
 chunk = sock.recv(msgLen - bytesRcvd)
 if chunk == "": break
 bytesRcvd += len(chunk)
 msg += chunk
 if "\r\n" in msg: break
 return msg
while True:
 read_sockets, write_sockets, error_sockets = select.select(connected_clients_sockets, [], [])
 for sock in read_sockets:
 if sock == server_socket:
 sockfd, client_address = server_socket.accept()
 connected_clients_sockets.append(sockfd)
 else:
 try:
 data = recvall(sock, 4096)
 if data:
 txt = data.strip()
 print '--%s--' % txt
 if txt == 'GET':
 sock.sendall('OK\r\n')
 elif txt == 'GET_SIZE':
 with open('tux.png', 'rb') as f1:
 file_size = len(f1.read())
 f1.seek(0)
 print '--%s--' % file_size
 file_size = '%s' % file_size
 sock.sendall('SIZE %s\r\n' % file_size)
 elif txt == 'GET_IMG':
 with open(image, 'rb') as fp:
 image_data = fp.read()
 msg = '%sEOIMG\r\n' % image_data
 sock.sendall(msg)
 elif txt == 'DONE':
 sock.close()
 connected_clients_sockets.remove(sock)
 except:
 sock.close()
 connected_clients_sockets.remove(sock)
 continue
server_socket.close()