Python 2.7 with pip install csa
Based on what I understand block() changes seed every time it is evoked so for

this results in the above.
However, for the same probability of success, here r = random(0.5) if we evoke block of the same size

and again

and so on ...
If block() re-seeds every time it is called, should all of the above look exactly the same?
PS: This issue is persistent also for python 3.7