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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 Ttr(x):
 """Equation for the triple point of ammonia-water mixture Parameters x : float Mole fraction of ammonia in mixture, [mol/mol] Returns ------- Ttr : float Triple point temperature, [K] Notes ------ Raise :class:`NotImplementedError` if input isn't in limit: * 0 ≤ x ≤ 1 References IAPWS, Guideline on the IAPWS Formulation 2001 for the Thermodynamic Properties of Ammonia-Water Mixtures, http://www.iapws.org/relguide/nh3h2o.pdf, Eq 9 """

    if 0 <= x <= 0.33367:
        Ttr = 273.16*(1-0.3439823*x-1.3274271*x**2-274.973*x**3)
    elif 0.33367 < x <= 0.58396:
        Ttr = 193.549*(1-4.987368*(x-0.5)**2)
    elif 0.58396 < x <= 0.81473:
        Ttr = 194.38*(1-4.886151*(x-2/3)**2+10.37298*(x-2/3)**3)
    elif 0.81473 < x <= 1:
        Ttr = 195.495*(1-0.323998*(1-x)-15.87560*(1-x)**4)
    else:
        raise NotImplementedError("Incoming out of bound")
    return Ttr