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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 nearest_neighbour_delta_E( self ):
 """ Nearest-neighbour interaction contribution to the change in system energy if this jump were accepted. Args: None Returns: (Float):
 delta E (nearest-neighbour) """

        delta_nn = self.final_site.nn_occupation() - self.initial_site.nn_occupation() - 1 # -1 because the hopping ion is not counted in the final site occupation number
        return ( delta_nn * self.nearest_neighbour_energy )