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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 _coligative(self, rho, A, fav):
 """Miscelaneous properties of humid air Parameters rho : float Density, [kg/m³] A : float Mass fraction of dry air in humid air, [kg/kg] fav : dict dictionary with helmholtz energy and derivatives Returns ------- prop : dict Dictionary with calculated properties: * mu: Relative chemical potential, [kJ/kg] * muw: Chemical potential of water, [kJ/kg] * M: Molar mass of humid air, [g/mol] * HR: Humidity ratio, [-] * xa: Mole fraction of dry air, [-] * xw: Mole fraction of water, [-] References IAPWS, Guideline on an Equation of State for Humid Air in Contact with Seawater and Ice, Consistent with the IAPWS Formulation 2008 for the Thermodynamic Properties of Seawater, Table 12, http://www.iapws.org/relguide/SeaAir.html """

        prop = {}
        prop["mu"] = fav["fira"]
        prop["muw"] = fav["fir"]+rho*fav["fird"]-A*fav["fira"]
        prop["M"] = 1/((1-A)/Mw+A/Ma)
        prop["HR"] = 1/A-1
        prop["xa"] = A*Mw/Ma/(1-A*(1-Mw/Ma))
        prop["xw"] = 1-prop["xa"]
        return prop