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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 view(grid):
    "Show a grid human-readably."
    p_mark, q_mark = player_marks(grid)
    return grid_format % tuple(p_mark if by_p else q_mark if by_q else '.'
                               for by_p, by_q in zip(*map(player_bits, grid)))