'Starts migrating from Tribler 6.3 to 6.4.'

def start_migrate(self):

    if (self.db.version == 17):
        self._upgrade_17_to_18()
    if (self.db.version == 18):
        self._upgrade_18_to_22()
    if (self.db.version == 22):
        self._upgrade_22_to_23()
    if (self.db.version == 23):
        self._upgrade_23_to_24()
    if (self.db.version == 24):
        self._upgrade_24_to_25()
    if (self.db.version == 25):
        self._upgrade_25_to_26()
    if (self.db.version == 26):
        self._upgrade_26_to_27()
    if (self.db.version == 27):
        self._upgrade_27_to_28()
    if (self.db.version == 28):
        self._upgrade_28_to_29()
    if (self.db.version == LATEST_DB_VERSION):
        self.status_update_func(u'Database    upgrade    finished.')
        self.failed = False
    elif (self.db.version < LOWEST_SUPPORTED_DB_VERSION):
        msg = (u'Database    is    too    old    %s    <    %s' % (self.db.version, LOWEST_SUPPORTED_DB_VERSION))
        self.status_update_func(msg)
        raise VersionNoLongerSupportedError(msg)
    else:
        msg = (u'Database    upgrade    failed:    %s    ->    %s' % (self.db.version, LATEST_DB_VERSION))
        self.status_update_func(msg)
        raise DatabaseUpgradeError(msg)
