def METHOD_NAME(argv):
    '''Replace placeholder release notes with the final release notes for a version.'''
    parser = argparse.ArgumentParser()
    parser.add_argument('filename', help='Path to release notes document')
    parser.add_argument('new_version', help='New version to use when updating the document')
    parser.add_argument('--overwrite', action='store_true', default=False, help='Overwrite the existing file if set')
    args = parser.parse_args(argv)
    new_contents = get_new_contents(args.filename, args.new_version)
    if args.overwrite:
        with open(args.filename, 'w') as fout:
            fout.write(new_contents)
        print 'Updated {} for version {}'.format(args.filename, args.new_version)
    else:
        print new_contents