import fileinput import sys file = 'core/templates/index.html' with open(file, "r+") as f: s = f.read() f.seek(0) f.write("{% load staticfiles %}\n" + s) for i, line in enumerate(fileinput.input(file, inplace=1)): sys.stdout.write(line.replace('/static/', "{% static '")) for i, line in enumerate(fileinput.input(file, inplace=1)): sys.stdout.write(line.replace('.css', ".css' %}")) for i, line in enumerate(fileinput.input(file, inplace=1)): sys.stdout.write(line.replace('.js', ".js' %}"))