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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 _select_vs(v, p):
 # This one is is about 30 times faster than # the generic algorithm it is replacing. """returns the points to use for interpolating v"""


    if v >= 120.:
        return 60, 120, inf
    elif v >= 60.:
        return 40, 60, 120
    elif v >= 40.:
        return 30, 40, 60
    elif v >= 30.:
        return 24, 30, 40
    elif v >= 24.:
        return 20, 24, 30
    elif v >= 19.5:
        return 19, 20, 24

    if p >= .9:
        if v < 2.5:
            return 1, 2, 3
    else:
        if v < 3.5:
            return 2, 3, 4

    vi = int(round(v))
    return vi - 1, vi, vi + 1