How to use the buku.parse_tags function in buku

def test_list_tags(capsys, setup):
    bdb = BukuDb()

    # adding bookmarks
    bdb.add_rec("http://one.com", "", parse_tags(['cat,ant,bee,1']), "")
    bdb.add_rec("http://two.com", "", parse_tags(['Cat,Ant,bee,1']), "")
    bdb.add_rec("http://three.com", "", parse_tags(['Cat,Ant,3,Bee,2']), "")

    # listing tags, asserting output
    out, err = capsys.readouterr()
    prompt(bdb, None, True, listtags=True)
    out, err = capsys.readouterr()
    assert out == "     1. 1 (2)\n     2. 2 (1)\n     3. 3 (1)\n     4. ant (3)\n     5. bee (3)\n     6. cat (3)\n\n"
    assert err == ''

# removing nonexistent tag which is also a substring of other tag
        with mock.patch('builtins.input', return_value='y'):
            self.bdb.replace_tag("e")

        for url, title, _, _ in self.bookmarks:
            # retrieving from db
            index = self.bdb.get_rec_id(url)
            from_db = self.bdb.get_rec_by_id(index)
            # asserting tags were replaced
            if title == "SLASHDOT":
                self.assertEqual(from_db[3], parse_tags(["__01"]))
            elif title == "ZAŻÓŁĆ":
                self.assertEqual(from_db[3], parse_tags(["__02,__03,jaźń"]))
            elif title == "test":
                self.assertEqual(from_db[3], parse_tags(["test,tes,est,__04"]))

def test_parse_tags(self):
        # call with None
        parsed = parse_tags(None)
        self.assertIsNone(parsed)
        # call with empty list
        parsed = parse_tags([])
        self.assertEqual(parsed, ",")
        # empty tags
        parsed = parse_tags([",,,,,"])
        self.assertEqual(parsed, ",")
        # sorting tags
        parsed = parse_tags(["z_tag,a_tag,n_tag"])
        self.assertEqual(parsed, ",a_tag,n_tag,z_tag,")
        # whitespaces
        parsed = parse_tags([" a tag , ,   ,  ,\t,\n,\r,\x0b,\x0c"])
        self.assertEqual(parsed, ",a tag,")
        # duplicates, excessive spaces
        parsed = parse_tags(["tag,tag, tag,  tag,tag , tag "])
        self.assertEqual(parsed, ",tag,")

'additional bookmark to test multiple tag search', 0]

        self.bdb.add_rec(*new_bookmark)

        with mock.patch('buku.prompt'):
            # search for bookmarks matching ANY of the supplied tags
            results = self.bdb.search_by_tag('test, old')
            # Expect a list of five-element tuples containing all bookmark data
            # db index, URL, title, tags, description, ordered by records with
            # the most number of matches.
            expected = [
                (4, 'https://newbookmark.com', 'New Bookmark',
                 parse_tags([',test,old,new,']),
                 'additional bookmark to test multiple tag search', 0),
                (1, 'http://slashdot.org', 'SLASHDOT',
                 parse_tags([',news,old,']),
                 "News for old nerds, stuff that doesn't matter", 0),
                (3, 'http://example.com/', 'test', ',es,est,tes,test,', 'a case for replace_tag test', 0)
            ]
            self.assertEqual(results, expected)

def test_search_by_tags_enforces_space_seprations_search_all(self):

        bookmark1 = ['https://bookmark1.com',
                     'Bookmark One',
                     parse_tags(['tag, two,tag+two']),
                     "test case for bookmark with '+' in tag"]

        bookmark2 = ['https://bookmark2.com',
                     'Bookmark Two',
                     parse_tags(['tag,two, tag-two']),
                     "test case for bookmark with hyphenated tag"]

        self.bdb.add_rec(*bookmark1)
        self.bdb.add_rec(*bookmark2)

        with mock.patch('buku.prompt'):
            # check that space separation for ' + ' operator is enforced
            results = self.bdb.search_by_tag('tag+two')
            # Expect a list of five-element tuples containing all bookmark data
            # db index, URL, title, tags, description
            expected = [

new_bookmark = ['https://newbookmark.com',
                        'New Bookmark',
                        parse_tags(['test,old,new']),
                        'additional bookmark to test multiple tag search']

        self.bdb.add_rec(*new_bookmark)

        with mock.patch('buku.prompt'):
            # search for bookmarks matching ALL of the supplied tags
            results = self.bdb.search_by_tag('test + old')
            # Expect a list of five-element tuples containing all bookmark data
            # db index, URL, title, tags, description
            expected = [
                (4, 'https://newbookmark.com', 'New Bookmark',
                 parse_tags([',test,old,new,']),
                 'additional bookmark to test multiple tag search', 0)
            ]
            self.assertEqual(results, expected)

'keywords, exp_res',
    [
        (None, None),
        ([], None),
        (['tag1', 'tag2'], ',tag1 tag2,'),
        (['tag1,tag2', 'tag3'], ',tag1,tag2 tag3,'),
    ]
)
def test_parse_tags(keywords, exp_res):
    """test func."""
    import buku
    if keywords is None:
        pass
    elif not keywords:
        exp_res = buku.DELIM
    res = buku.parse_tags(keywords)
    assert res == exp_res

def test_search_by_tags_enforces_space_seprations_exclusion(self):

        bookmark1 = ['https://bookmark1.com',
                     'Bookmark One',
                     parse_tags(['tag, two,tag+two']),
                     "test case for bookmark with '+' in tag"]

        bookmark2 = ['https://bookmark2.com',
                     'Bookmark Two',
                     parse_tags(['tag,two, tag-two']),
                     "test case for bookmark with hyphenated tag"]

        bookmark3 = ['https://bookmark3.com',
                     'Bookmark Three',
                     parse_tags(['tag, tag three']),
                     "second test case for bookmark with hyphenated tag"]

        self.bdb.add_rec(*bookmark1)
        self.bdb.add_rec(*bookmark2)
        self.bdb.add_rec(*bookmark3)

        with mock.patch('buku.prompt'):
            # check that space separation for ' - ' operator is enforced
            results = self.bdb.search_by_tag('tag-two')
            # Expect a list of five-element tuples containing all bookmark data
            # db index, URL, title, tags, description
            expected = [
                (2, 'https://bookmark2.com', 'Bookmark Two',
                 parse_tags([',tag,two,tag-two,']),
                 "test case for bookmark with hyphenated tag", 0),
            ]

'additional bookmark to test multiple tag search']

        self.bdb.add_rec(*new_bookmark)

        with mock.patch('buku.prompt'):
            # search for bookmarks matching ANY of the supplied tags
            # while excluding bookmarks from results that match a given tag
            results = self.bdb.search_by_tag('test, old - est')
            # Expect a list of five-element tuples containing all bookmark data
            # db index, URL, title, tags, description
            expected = [
                (4, 'https://newbookmark.com', 'New Bookmark',
                 parse_tags([',test,old,new,']),
                 'additional bookmark to test multiple tag search', 0),
                (1, 'http://slashdot.org', 'SLASHDOT',
                 parse_tags([',news,old,']),
                 "News for old nerds, stuff that doesn't matter", 0),
            ]
            self.assertEqual(results, expected)