cpimport string with \ and \\ in the end

/usr/local/mariadb/columnstore/bin/cpimport r8 test /var/spin_sync/test1 -E '|' -s '\t' -C '\' -e 4000

we can't load this file without errors.
in case of changing escaped character it is not possible to define escape character that file doesn't contain at the end of the URL field.