import sys, re
file = open("c:/sample.txt", "r")
newfile = open("c:/sample2.txt", "w")
contents = file.read()
def dashrepl(matchobj):
     newfile.write(matchobj.group(1) + "\n")	
     return matchobj.group(1)
re.sub(".*?({{(U|u)delh}}.*?{{(U|u)delf}}).*?", dashrepl, contents)
newfile.close();
file.close()