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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):
 """scalar version of psturng"""

    if q < 0.:
        raise ValueError('q should be >= 0')

    opt_func = lambda p, r, v : abs(_qsturng(p, r, v) - q)

    if v == 1:
        if q < _qsturng(.9, r, 1):
            return .1
        elif q > _qsturng(.999, r, 1):
            return .001
        return 1. - fminbound(opt_func, .9, .999, args=(r,v))
    else:
        if q < _qsturng(.1, r, v):
            return .9
        elif q > _qsturng(.999, r, v):
            return .001
        return 1. - fminbound(opt_func, .1, .999, args=(r,v))