what is XXX encode method in javascript

there is a string like :

"2311222241164620127275337153163715226626430024"

when I log it in js console, its decoded form is:

'x99Rx94N&x10W½ßks9*¶´Àx14'

I’ve searched a lot but couldn’t find what encode/decode method is, in js its automatically converted. I need to converted this string in python