target.write("%s \n %s \n %s \") % (line1, line2, line3)

#giver dette output.

[root@daniel-pc code]# python ex16.py test.txt
  File "ex16.py", line 27
    target.write("%s \n %s \n %s \") % (line1, line2, line3)
                                                           ^
SyntaxError: EOL while scanning string literal