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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 psturng(q, r, v):
 """Evaluates the probability from 0 to q for a studentized range having v degrees of freedom and r samples. Parameters q : (scalar, array_like) quantile value of Studentized Range q >= 0. r : (scalar, array_like) The number of samples r >= 2 and r <= 200 (values over 200 are permitted but not recommended) v : (scalar, array_like) The sample degrees of freedom if p >= .9: v >=1 and v >= inf else: v >=2 and v >= inf Returns ------- p : (scalar, array_like) 1. - area from zero to q under the Studentized Range distribution. When v == 1, p is bound between .001 and .1, when v > 1, p is bound between .001 and .9. Values between .5 and .9 are 1st order appoximations. """

    if all(map(_isfloat, [q, r, v])):
        return _psturng(q, r, v)
    return _vpsturng(q, r, v)