backslash at the end of string causing error

INSERT INTO default VALUES("k01",{"a":1});

UPDATE  default AS d USE KEYS  "k01" 

SET description= "John's words  are \"Never give up\". blackslash \\", title="xyz";

UPDATE  default AS d USE KEYS  "k01" 

SET description= "John's words  are \"Never give up\". blackslash \\.", title="xyz";

UPDATE  default AS d USE KEYS  "k01" 

SET description= "John's words  are \"Never give up\". blackslash \\ ", title="xyz";

UPDATE  default AS d USE KEYS  "k01" 

SET description= "John's words  are \"Never give up\". blackslash \\", title='xyz';