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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def par_final_stepgrp(i):
 """The parallel step grouping of the final iteration in solve. A cyclic permutation of the steps is done to require only one merge per iteration, requiring unique initial and final step groups. Parameters i : int Index of grouping to update """


    par_y0bstep(i)
    par_y1step(i)
    par_u0step(i)
    par_u1step(i)