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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 get_monolayer(self):
 """ Returns the primitive unit surface area density of the adsorbate. """


        unit_a = self.get_unit_primitive_area
        Nsurfs = self.Nsurfs_ads_in_slab
        Nads = self.Nads_in_slab
        return Nads / (unit_a * Nsurfs)