Hi there, here is my thoughts..
Hello, I am a neighbor and I have noticed that you tend to have parties, but can you please consider keeping the noise down? The loud partying is disrupting me not to be able to properly study, which will affect my grades, come test taking time. This disturbance has been going on recently, and I would hope you can take this into a consideration and turn down your music.
I know this isn't the best letter nor close, but I hope this helps you :)