Client need to notify that it finished sending, using socket.shutdown (not socket.close which close both reading/writing part of the socket):
...
print "Done Sending"
s.shutdown(socket.SHUT_WR)
print s.recv(1024)
s.close()
UPDATE
Client sends Hello server! to the server; which is written to the file in the server side.
s.send("Hello server!")
Remove above line to avoid it.