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Stream Cipher Challenge Day

OK, I want to get some mojo back so let's do a hands on cracking day.

Partner Up: Pick a partner at a different table. Exchange a secret phrase which will be your shared secret (confirm capitalizations and spacing). Distinguish one of you as person 1 and the other as person 2.
Generate a message each: Use less than 24 characters for today.
Each Partner makes a nonce Partners generate a 6 byte nonce using os.urandom(6). Use my gist (below) and your secret phrase to secretly go from NONCE to seed.
Send a dummy message: Use your NONCE to send the message "this is a dummy message." attach your NONCE as the first 6 bytes of the ciphertext.
Use the NONCE again: Now use the same nonce to send your secret messages that you picked out.
Decrypt your partner's message If you get it you'll know.
Pick an opposing team. Decrypt their messages because you knew the dummy message and they used the same NONCE twice.

Utility Code

Fully Functioning Code

The Challenge In CTF Style:

A Ninja XOR Challenge To Practice