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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 _sec_to_str(t):
 """Format time in seconds. Parameters t : int Time in seconds. """

    from functools import reduce
    return "%d:%02d:%02d.%02d" % \
        reduce(lambda ll, b: divmod(ll[0], b) + ll[1:],
               [(t*100,), 100, 60, 60])