try this

#! /usr/bin/env python

## Use the script to help get tracker information from Nuke to Shake.  It will alter data written out
## of Nuke and re-format it to be read by Shake.
## Justin Ball
## 20090506

import sys, os.path, string



if len(sys.argv) <= 1:
    print "Please attach a file path to the Nuke tracker file when running the script"
    nukeFile = raw_input("Please provide a path to the file now: ")
    if nukeFile == "":
        print "\nNo File, we will now exit.\n"
        sys.exit(0)

if isfile(sys.argv[1]):
    nukeFile = sys.argv[1]

lineNumber = "1"
incr = "1"
correlationValue = '1.000'




baseName = os.path.basename(nukeFile)

dirName = os.path.dirname(nukeFile)

nukeFileName = []
nukeFileName = string.split(baseName, '.')

outFile = nukeFileName[0] + "_shake" + ".txt"

outFile = os.path.join(dirName, outFile)
print outFile
readFile = open(nukeFile, 'r').readlines()



write = open(outFile, 'w')
write.write("TrackName track1\n")
write.write("   Frame \t X \t Y \t Correlation\n")

for line in readFile:
    values = string.split(line, " ")
    values1 = string.strip(values[1], "\n")


    newLineNumber = str(lineNumber) + ".00" 


    newLine = ("   " + str(newLineNumber) + "    " + str(values[0]) + "    " + str(values1) + "    " + correlationValue + "\n")
    print newLine
    write.write(newLine)
    lineNumber = int(lineNumber) + 1



print "Done"