Rename all files in a directory with a prefix

prefix_all_files_in_directory.py

import os
directory = "/home/james/images"
extension = ".jpg"
prefix = "prefix_"
for filename in os.listdir(directory):
    if not filename.endswith(extension):
        continue
    new_filename = prefix + filename
    old_file_path = os.path.join(directory, filename)
    new_file_path = os.path.join(directory, new_filename)
    os.rename(old_file_path, new_file_path)