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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 normal_range(mean, sd, treshold=1.28):
 """ Returns a bottom and a top limit on a normal distribution portion based on a treshold. Parameters treshold : float maximum deviation (in terms of standart deviation). Rule of thumb of a gaussian distribution: 2.58 = keeping 99%, 2.33 = keeping 98%, 1.96 = 95% and 1.28 = keeping 90%. Returns (bottom, top) : tuple Lower and higher range. Example Notes *Authors* - `Dominique Makowski <https://dominiquemakowski.github.io/>`_ """

    bottom = mean - sd*treshold
    top = mean + sd*treshold
    return(bottom, top)