Maybe, If you forgot it and you don't wanna use the reset password option. But in fact, It's a fun tweak to realize RadioJavan knows your password.
First of all you have to install Radio Javan and after login, you are free to use this tweak. https://apps.apple.com/us/app/radio-javan/id286225933
You can compile and install it on your device or download and install it directly from my repo: http://Nimk.ir/repo