/fit/izens of this board, lo and listen to my struggle, for it is real and I can't even!

I'm traveling for a bit, only got light luggage on me and obviously no weights. therefore I was planning to make some body weight exercises in the evening, so I won't lose to much mass. unfortunately I just realized that I know not a single exercise to train my biceps (that doesn't at least require a pole which I often don't have).

Please help me out, I might lose all my gains!!!