Python - Way to recursively find and replace string in text files

Question

I want to recursively search through a directory with subdirectories of text files and replace every occurrence of {$replace} within the files with the contents of a multi l

Answer 1

Multiple files string change

import glob

for allfiles in glob.glob('*.txt'):

for line in open(allfiles,'r'):
    change=line.replace("old_string","new_string")
    output=open(allfiles,'w')
    output.write(change)