How to use the castero.subscriptions.Subscriptions function in castero

def test_subscriptions_save():
    temp_fname = my_dir + "/subscriptions/saved_temp.xml"
    Feed.__init__ = mock.MagicMock(return_value=None)

    mysubscriptions1 = Subscriptions()
    mysubscriptions1.load(my_dir + "/subscriptions/valid_complete.xml")
    mysubscriptions1.save(temp_fname)

    mysubscriptions2 = Subscriptions()
    mysubscriptions2.load(my_dir + "/subscriptions/saved_temp.xml")
    os.remove(temp_fname)

    tree1 = ElementTree.tostring(mysubscriptions1._tree.getroot())
    tree2 = ElementTree.tostring(mysubscriptions2._tree.getroot())
    assert tree1 == tree2

def test_subscriptions_save():
    temp_fname = my_dir + "/subscriptions/saved_temp.xml"
    Feed.__init__ = mock.MagicMock(return_value=None)

    mysubscriptions1 = Subscriptions()
    mysubscriptions1.load(my_dir + "/subscriptions/valid_complete.xml")
    mysubscriptions1.save(temp_fname)

    mysubscriptions2 = Subscriptions()
    mysubscriptions2.load(my_dir + "/subscriptions/saved_temp.xml")
    os.remove(temp_fname)

    tree1 = ElementTree.tostring(mysubscriptions1._tree.getroot())
    tree2 = ElementTree.tostring(mysubscriptions2._tree.getroot())
    assert tree1 == tree2

def test_subscriptions_broken_parse():
    mysubscriptions = Subscriptions()
    Feed.__init__ = mock.MagicMock(return_value=None)
    with pytest.raises(SubscriptionsParseError):
        mysubscriptions.load(my_dir + "/subscriptions/broken_parse.xml")

def test_subscriptions_valid_no_head():
    mysubscriptions = Subscriptions()
    Feed.__init__ = mock.MagicMock(return_value=None)
    mysubscriptions.load(my_dir + "/subscriptions/valid_no_head.xml")
    assert isinstance(mysubscriptions, Subscriptions)
    Feed.__init__.assert_any_call(url="http://feed1")
    Feed.__init__.assert_any_call(url="http://feed2")
    assert Feed.__init__.call_count == 2
    assert len(mysubscriptions.feeds) == 2

def test_subscriptions_valid_minimal():
    mysubscriptions = Subscriptions()
    Feed.__init__ = mock.MagicMock(return_value=None)
    mysubscriptions.load(my_dir + "/subscriptions/valid_minimal.xml")
    assert isinstance(mysubscriptions, Subscriptions)
    assert len(mysubscriptions.feeds) == 0

def test_subscriptions_generate():
    feed1 = mock.MagicMock()
    feed2 = mock.MagicMock()
    mysubscriptions = Subscriptions()
    mysubscriptions.generate([feed1, feed2])

    Feed.__init__ = mock.MagicMock(return_value=None)
    mysubscriptions._parse_feeds()
    assert len(mysubscriptions.feeds) == 2

def test_subscriptions_valid_base():
    mysubscriptions = Subscriptions()
    Feed.__init__ = mock.MagicMock(return_value=None)
    mysubscriptions.load(my_dir + "/subscriptions/valid_base.xml")
    assert isinstance(mysubscriptions, Subscriptions)
    Feed.__init__.assert_any_call(url="http://feed1")
    Feed.__init__.assert_any_call(url="http://feed2")
    assert Feed.__init__.call_count == 2
    assert len(mysubscriptions.feeds) == 2

def import_subscriptions(path: str, database: Database) -> None:
    subscriptions = Subscriptions()

    # Load may raise an error, but they are user-friendly enough that we don't
    # need to catch them here. It's also okay to crash at this point.
    subscriptions.load(path)

    print("Importing %d feeds..." % len(subscriptions.feeds))

    for feed in subscriptions.feeds:
        database.replace_feed(feed)
        episodes = feed.parse_episodes()
        database.replace_episodes(feed, episodes)
        print("Imported '%s' with %d episodes" % (str(feed), len(episodes)))

def export_subscriptions(path: str, database: Database) -> None:
    subscriptions = Subscriptions()

    feeds = database.feeds()
    subscriptions.generate(feeds)
    # Save may raise an error, but they are user-friendly enough that we don't
    # need to catch them here. It's also okay to crash at this point.
    subscriptions.save(path)

    print("Exported %d feeds" % len(feeds))