How to use the mike.versions.VersionInfo function in mike

def test_equality(self):
        v = VersionInfo('1.0')
        self.assertEqual(v, VersionInfo('1.0'))
        self.assertNotEqual(v, VersionInfo('1.1'))
        self.assertNotEqual(v, VersionInfo('1.0', '1.0.0'))
        self.assertNotEqual(v, VersionInfo('1.0', aliases=['latest']))

        v = VersionInfo('1.0', '1.0.0')
        self.assertNotEqual(v, VersionInfo('1.0'))
        self.assertNotEqual(v, VersionInfo('1.1'))
        self.assertEqual(v, VersionInfo('1.0', '1.0.0'))
        self.assertNotEqual(v, VersionInfo('1.0', aliases=['latest']))

        v = VersionInfo('1.0', aliases=['latest'])
        self.assertNotEqual(v, VersionInfo('1.0'))
        self.assertNotEqual(v, VersionInfo('1.1'))
        self.assertNotEqual(v, VersionInfo('1.0', '1.0.0'))
        self.assertEqual(v, VersionInfo('1.0', aliases=['latest']))

message = subprocess.check_output(['git', 'log', '-1', '--pretty=%B'],
                                          universal_newlines=True).rstrip()
        if expected_message:
            self.assertEqual(message, expected_message)
        else:
            self.assertRegex(message,
                             r'^Set title of \S+ to 1\.0\.1 with mike \S+$')

        assertDirectory('.', {
            'versions.json',
            '1.0',
            '1.0/file.txt'
        })
        with open('versions.json') as f:
            self.assertEqual(list(versions.Versions.loads(f.read())), [
                versions.VersionInfo('1.0', '1.0.1'),
            ])

def test_remove_version(self):
        versions = Versions()
        versions.add('1.0')
        v = versions.remove('1.0')
        self.assertEqual(v, VersionInfo('1.0'))
        self.assertEqual(list(versions), [])

def test_add(self):
        versions = Versions()
        v = versions.add('1.0')
        self.assertEqual(v, VersionInfo('1.0'))
        self.assertEqual(list(versions), [
            VersionInfo('1.0'),
        ])

def test_update_alias_aliases(self):
        versions = Versions()
        versions.add('1.0', '1.0.0', ['latest'])
        diff = versions.update('latest', aliases=['greatest'])
        self.assertEqual(diff, {'greatest'})
        self.assertEqual(list(versions), [
            VersionInfo('1.0', '1.0.0', ['latest', 'greatest']),
        ])

def test_equality(self):
        v = VersionInfo('1.0')
        self.assertEqual(v, VersionInfo('1.0'))
        self.assertNotEqual(v, VersionInfo('1.1'))
        self.assertNotEqual(v, VersionInfo('1.0', '1.0.0'))
        self.assertNotEqual(v, VersionInfo('1.0', aliases=['latest']))

        v = VersionInfo('1.0', '1.0.0')
        self.assertNotEqual(v, VersionInfo('1.0'))
        self.assertNotEqual(v, VersionInfo('1.1'))
        self.assertEqual(v, VersionInfo('1.0', '1.0.0'))
        self.assertNotEqual(v, VersionInfo('1.0', aliases=['latest']))

        v = VersionInfo('1.0', aliases=['latest'])
        self.assertNotEqual(v, VersionInfo('1.0'))
        self.assertNotEqual(v, VersionInfo('1.1'))
        self.assertNotEqual(v, VersionInfo('1.0', '1.0.0'))
        self.assertEqual(v, VersionInfo('1.0', aliases=['latest']))

def add(self, version, title=None, aliases=[], update_aliases=False):
        v = _ensure_version(version)
        removed_aliases = []
        for i in aliases:
            key = self.find(i)
            if key and key[0] != v:
                if not update_aliases or len(key) == 1:
                    raise ValueError('{!r} already exists'.format(i))
                removed_aliases.append(key)

        if v in self._data:
            self._data[v].update(title, aliases)
        else:
            if self.find(version):
                raise ValueError('{!r} already exists'.format(version))
            self._data[v] = VersionInfo(version, title, aliases)

        for i in removed_aliases:
            self._data[i[0]].aliases.remove(i[1])

        return self._data[v]