How to select random from list while excluding the previous random choice?

I am trying to create a script that will allow me to play, from a list, a random christmas radio station using mpg123 upon button press. The problem I am running into is that, many times, the same radio station will play. I am messing around with lists, but having trouble getting it to work. I dont have the button wired just yet, so I am having the script pause and go again. Here are the stations so far..

station1 = "http://185.33.21.112:80/christmas_128"
station2 = "http://71.127.174.26:8020/hollyfm2"
station3 = "http://76.115.146.246:8128"
station4 = "http://85.25.217.22:8050/christmas"

station_list = [station1, station2, station3, station4]

Any help would be appreciated!