$ pip install changewords

usage: changewords.py [-h] [-p PATH] [-ft FILE_TYPE] [-fs FROM_STRING]
                      [-ts TO_STRING]

Python tool to change or replace the strings in files.

optional arguments:
  -h, --help            show this help message and exit
  -p PATH, --path PATH  the starting path or parent path name
                        by default is current path/folder.
  -ft FILE_TYPE, --file_type FILE_TYPE
                        file type you are looking for, eg: '.py', '.txt'
                        by default is '.py' (python files)
  -fs FROM_STRING, --from_string FROM_STRING
                        the string to change/replace
  -ts TO_STRING, --to_string TO_STRING
                        the string replacement

$ changewords -p=changewords_test -ft=.py -fs=helloworld -ts=mantabjiwa

# or

$ changewords --path=changewords_test --file_type=.py --from_string=helloworld --to_string=mantabjiwa

$ python tests.py