If you want to be able to use that script on many files, it is best to pass the file name as an argument so you can use the same script for all the files to be processed.
Ọ bụrụ na ịchọrọ iji edemede ahụ na ọtụtụ faịlụ, ọ kacha mma ka ịnyefe faịlụ aha dị ka esemokwu, ka i wee nwee ike iji otu edemede ahụ maka faịlụ niile a ga-edozi.