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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_partial_filling(self, propname):
 r""" Define which pore filling model to apply. Parameters propname : string Dictionary key on the physics object(s) containing the pore filling model(s) to apply. Notes ----- It is assumed that these models are functions of the `quantity` specified in the algorithms settings. This values is applied to the corresponding phase just prior to regenerating the given pore-scale model(s). """

        if propname.startswith('pore'):
            self.settings['pore_partial_filling'] = propname
        if propname.startswith('throat'):
            self.settings['throat_partial_filling'] = propname