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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 _critNaCl(x):
 """Equation for the critical locus of aqueous solutions of sodium chloride Parameters x : float Mole fraction of NaCl, [-] Returns ------- prop : dict A dictionary withe the properties: * Tc: critical temperature, [K] * Pc: critical pressure, [MPa] * rhoc: critical density, [kg/m³] Notes ------ Raise :class:`NotImplementedError` if input isn't in limit: * 0 ≤ x ≤ 0.12 Examples -------- 975.571016 References IAPWS, Revised Guideline on the Critical Locus of Aqueous Solutions of Sodium Chloride, http://www.iapws.org/relguide/critnacl.html """

    # Check input parameters
    if x < 0 or x > 0.12:
        raise NotImplementedError("Incoming out of bound")

    T1 = Tc*(1 + 2.3e1*x - 3.3e2*x**1.5 - 1.8e3*x**2)
    T2 = Tc*(1 + 1.757e1*x - 3.026e2*x**1.5 + 2.838e3*x**2 - 1.349e4*x**2.5 +
             3.278e4*x**3 - 3.674e4*x**3.5 + 1.437e4*x**4)
    f1 = (abs(10000*x-10-1)-abs(10000*x-10+1))/4+0.5
    f2 = (abs(10000*x-10+1)-abs(10000*x-10-1))/4+0.5

    # Eq 1
    tc = f1*T1+f2*T2

    # Eq 7
    rc = rhoc*(1 + 1.7607e2*x - 2.9693e3*x**1.5 + 2.4886e4*x**2 -
               1.1377e5*x**2.5 + 2.8847e5*x**3 - 3.8195e5*x**3.5 +
               2.0633e5*x**4)

    # Eq 8
    DT = tc-Tc
    pc = Pc*(1+9.1443e-3*DT+5.1636e-5*DT**2-2.5360e-7*DT**3+3.6494e-10*DT**4)

    prop = {}
    prop["Tc"] = tc
    prop["rhoc"] = rc
    prop["Pc"] = pc
    return prop