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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 set_cn_energies( self, cn_energies ):
 """ Set the coordination number dependent energies for this lattice. Args: cn_energies (Dict(Str:Dict(Int:Float))):
 Dictionary of dictionaries specifying the coordination number dependent energies for each site type. e.g.:: { 'A' : { 0 : 0.0, 1 : 1.0, 2 : 2.0 }, 'B' : { 0 : 0.0, 1 : 2.0 } } Returns: None """

        for site in self.sites:
            site.set_cn_occupation_energies( cn_energies[ site.label ] )
        self.cn_energies = cn_energies