Anyone good at breaking codes?

[NinjaJc01]

I have a little "encryption" program I wrote in python, and I want to know if anyone can crack it.

There are a few important stages to the encryption, and a key number you will need is 124. Each item in the list is one character, and the ";" is the middle of the list.

JVGS,GPBB,NZXS,NPBV,GJXN,PGSJ,GXNB,GVJJ,NXNV,PGSJ,GXNB,NGOS,GPBB,NZXS,GOZS,VZNV,PPOGN,NGOS,PZVJ,PPOGN,JGJB,GPBB,GVJJ,PPOGN,PGSJ,GJXN,PVSB,PPOGN,GJXN,PVSB,PGSJ;PXGS,NGOS,NZXS,NPBV,PPOGN,GXNB,NNGN,NGOS,GOZS,VZNV,PPOGN,GXNB,NNGN,PVSB,NZXS,PPOGN,JGJB,GPBB,GVJJ,PPOGN,NNGN,PGSJ,GZSV,PVSB,PPOGN,GOZS,NSBJ,NGOS,NXNV,NXNV,GOZS

 

[Thunderjolt]

Maybe this would be better in the programming sub forum