How to use the ubelt.ensure_app_cache_dir function in ubelt

def test_static_import_without_init():
    """
    python ~/code/mkinit/tests/test_with_dummy.py test_static_import_without_init
    """
    import mkinit
    cache_dpath = ub.ensure_app_cache_dir('mkinit/tests')
    paths = make_dummy_package(cache_dpath)
    ub.delete(paths['root_init'])

    modpath = paths['root']
    text = mkinit.static_init(modpath)
    check_dummy_root_init(text)

def test_dynamic_init():
    """
    python ~/code/mkinit/tests/test_with_dummy.py test_dynamic_init
    """
    import mkinit
    cache_dpath = ub.ensure_app_cache_dir('mkinit/tests')
    paths = make_dummy_package(cache_dpath, 'dynamic_dummy_mod1')
    module = ub.import_module_from_path(paths['root'])
    text = mkinit.dynamic_mkinit.dynamic_init(module.__name__)
    print(text)
    for i in range(1, 15):
        want = 'good_attr_{:02d}'.format(i)
        assert want in text, 'missing {}'.format(want)

def test_static_init():
    """
    python ~/code/mkinit/tests/test_with_dummy.py test_static_import_without_init
    """
    import mkinit
    cache_dpath = ub.ensure_app_cache_dir('mkinit/tests')
    paths = make_dummy_package(cache_dpath)

    modpath = paths['root']
    text = mkinit.static_init(modpath)
    check_dummy_root_init(text)

def test_static_find_locals():
    """
    python ~/code/mkinit/tests/test_with_dummy.py test_static_find_locals
    """
    import mkinit
    cache_dpath = ub.ensure_app_cache_dir('mkinit/tests')
    paths = make_dummy_package(cache_dpath)
    ub.delete(paths['root_init'])
    modpath = paths['root']
    imports = list(mkinit.static_mkinit._find_local_submodules(modpath))
    print('imports = {!r}'.format(imports))

def test_hash_file():
    fpath = join(ub.ensure_app_cache_dir('ubelt'), 'tmp.txt')
    ub.writeto(fpath, 'foobar')
    hashid1_a = ub.hash_file(fpath, hasher='sha512', hashlen=8, stride=1, blocksize=1)
    hashid2_a = ub.hash_file(fpath, hasher='sha512', hashlen=8, stride=2, blocksize=1)

    hashid1_b = ub.hash_file(fpath, hasher='sha512', hashlen=8, stride=1, blocksize=10)
    hashid2_b = ub.hash_file(fpath, hasher='sha512', hashlen=8, stride=2, blocksize=10)

    assert hashid1_a == hashid1_b
    assert hashid2_a != hashid2_b, 'blocksize matters when stride is > 1'
    assert hashid1_a != hashid2_a

def test_ensuredir_recreate():
    base = ub.ensure_app_cache_dir('ubelt/tests')
    folder = join(base, 'foo')
    member = join(folder, 'bar')
    ub.ensuredir(folder, recreate=True)
    ub.ensuredir(member)
    assert exists(member)
    ub.ensuredir(folder, recreate=True)
    assert not exists(member)

def test_pathlib():
    try:
        import pathlib
        base = pathlib.Path(ub.ensure_app_cache_dir('ubelt'))
        dpath = base.joinpath('test_pathlib_mkdir')

        # ensuredir
        ub.delete(dpath)
        assert not dpath.exists()
        got = ub.ensuredir(dpath)
        assert got.exists()

        # shrinkuser
        assert ub.shrinkuser(base) == '~/.cache/ubelt'

        assert ub.augpath(base, prefix='foo') == '/home/joncrall/.cache/fooubelt'

        ub.expandpath(base)

    except Exception:

>>> ub.download(url, hasher='sha512', hash_prefix='c98a46cb31205cf')
        >>> with pytest.raises(RuntimeError):
        >>>     ub.download(url, hasher='sha512', hash_prefix='BAD_HASH')
    """
    from ubelt import ProgIter as Progress
    from ubelt import ensure_app_cache_dir
    import shutil
    import tempfile
    import hashlib

    if six.PY2:  # nocover
        from urllib2 import urlopen  # NOQA
    else:
        from urllib.request import urlopen  # NOQA
    if fpath is None:
        dpath = ensure_app_cache_dir('ubelt')
        fname = basename(url)
        fpath = join(dpath, fname)

    _dst_is_io_object = hasattr(fpath, 'write')

    if verbose:
        if _dst_is_io_object:
            print('Downloading url=%r to IO object' % (url,))
        else:
            print('Downloading url=%r to fpath=%r' % (url, fpath))

    urldata = urlopen(url)
    meta = urldata.info()
    try:
        if hasattr(meta, 'getheaders'):  # nocover
            file_size = int(meta.getheaders("Content-Length")[0])