def download_files(client, source, destination, relative_directory):
    """ Download files from the remote directory.

    This method downloads one file, an entire directory or a set of
    files (specified by shell glob pattern) to a given directory in
    in the local filesystem. Additional parameters are there to
    refine the process.

    The source parameter refers to the remote file(s) to be
    transfered to the local filesystem and is expected to be a
    path-like object, unless it's a shell glob pattern in which case
    a string is expected. The path must be relative and is by
    default relative to the root directory. It can be
    altered with the relative_directory parameter which itself must
    be path-like object refering to an absolute directory.

    The destination parameter refers to the remote directory in
    which the file(s) must be transfered to. It must be a path-like
    object and must be absolute.

    Long description.

    :param source: Foobar.
    :param destination: Foobar.
    :param chunk_size: Foobar.
    :type chunk_size: int
    :param process_chunk: Foobar.
    :param timeout: How many milliseconds to wait before giving up
    :type timeout: int
    """
    pass
