def get_file(fname, origin, untar=False):
    datadir_base = os.path.expanduser(os.path.join('~', '.keras'))
    if not os.access(datadir_base, os.W_OK):
        datadir_base = os.path.join('/tmp', '.keras')
    datadir = os.path.join(datadir_base, 'datasets')
    if not os.path.exists(datadir):
        os.makedirs(datadir)

    if untar:
        untar_fpath = os.path.join(datadir, fname)
        fpath = untar_fpath + '.tar.gz'
    else:
        fpath = os.path.join(datadir, fname)

    if not os.path.exists(fpath):
        print('Downloading data from',  origin)
        global progbar
        progbar = None

        def dl_progress(count, block_size, total_size):
            global progbar
            if progbar is None:
                progbar = Progbar(total_size)
            else:
                progbar.update(count*block_size)

        error_msg = 'URL fetch failure on {}: {} -- {}'
        try:
            try:
                urlretrieve(origin, fpath, dl_progress)
            except URLError as e:
                raise Exception(error_msg.format(origin, e.errno, e.reason))
            except HTTPError as e:
                raise Exception(error_msg.format(origin, e.code, e.msg))
        except (Exception, KeyboardInterrupt) as e:
            if os.path.exists(fpath):
                os.remove(fpath)
            raise
        progbar = None

    if untar:
        if not os.path.exists(untar_fpath):
            print('Untaring file...')
            tfile = tarfile.open(fpath, 'r:gz')
            try:
                tfile.extractall(path=datadir)
            except (Exception, __HOLE__) as e:
                if os.path.exists(untar_fpath):
                    if os.path.isfile(untar_fpath):
                        os.remove(untar_fpath)
                    else:
                        shutil.rmtree(untar_fpath)
                raise
            tfile.close()
        return untar_fpath

    return fpath
dataset/ETHPy150Open fchollet/keras/keras/utils/data_utils.py/get_file