random module in while loops

[Mekire]

You need to set a seed. See https://docs.python.org/3.6/library/random.html

the syntax is

random.seed()

That really shouldn't be the issue.  The random module is seeded initially regardless (with a call to the systems clock I believe).  Subsequent calls to random.randint shouldn't give the same value because of this.  Providing your own seed is generally only needed if you want to be able to have deterministic behavior.  

I think the issue here is simply typos:

       u1move = u1step + u1jump
       u1step = u1move
       u2move = u2step + u1jump
       u2step = u2move
       u3move = u3step + u1jump
       u3step = u3move

I'm guessing those u1jump's should be u2jump and u3jump for u2move and u3move respectively.