def main(file_in, file_out):
    """
    Read in lines, sort lines, write out sorted lines.
    """

    with open(file_in, 'r') as f_in:
        lines = [line for line in f_in]

    with open(file_out, 'w') as f_out:
        for string in sorted(lines):
            f_out.write(string)

    return None