Edit in place

inputfile.txt

goodbye
hello
see you later!

edit.py

import fileinput
for lines in fileinput.FileInput("inputfile.txt", inplace=1): ## edit file in place
    lines = lines.replace("hello","hi")
    print lines.replace('\n','') ## although this prints the line, the file will be modified.

inputfile.txt

goodbye
hi
see you later!

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