Remove Duplicate Line in Vim?

Question

I\'m trying to use VIM to remove a duplicate line in an XML file I created. (I can\'t recreate the file because the ID numbers will change.)

The file looks something

Answer 1

with python to remove all repeated lines:

#!/usr/bin/env python

import sys
def remove_identical(filein, fileout) : 
  lines = list()
  for line in open(filein, 'r').readlines() : 
    if line not in lines : lines.append(line)
  fout = open(fileout, 'w')
  fout.write(''.join(lines))
  fout.close()

remove_identical(sys.argv[1], sys.argv[2])