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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 pacl_term(DiamTube, ConcClay, ConcAl, ConcNatOrgMat, NatOrgMat, coag, material, RatioHeightDiameter):
 """Return the fraction of the surface area that is covered with coagulant that is not covered with humic acid. :param DiamTube: Diameter of the dosing tube :type Diamtube: float :param ConcClay: Concentration of clay in solution :type ConcClay: float :param ConcAl: Concentration of alumninum in solution :type ConcAl: float :param ConcNatOrgMat: Concentration of natural organic matter in solution :type ConcNatOrgMat: float :param NatOrgMat: type of natural organic matter, e.g. floc_model.HumicAcid :type NatOrgMat: floc_model.Material :param coag: Type of coagulant in solution, e.g. floc_model.PACl :type coag: floc_model.Material :param material: Type of clay in suspension, e.g. floc_model.Clay :type material: floc_model.Material :param RatioHeightDiameter: Dimensionless ratio of clay height to clay diameter :type RatioHeightDiameter: float :return: fraction of the surface area that is covered with coagulant that is not covered with humic acid :rtype: float """

    return (gamma_coag(ConcClay, ConcAl, coag, material, DiamTube,
                       RatioHeightDiameter)
            * (1 - gamma_humic_acid_to_coag(ConcAl, ConcNatOrgMat,
                                            NatOrgMat, coag))
            )