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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 relative_probability( self, l1, l2, c1, c2 ):
 """ The relative probability for a jump between two sites with specific site types and coordination numbers. Args: l1 (Str):
 Site label for the initial site. l2 (Str):
 Site label for the final site. c1 (Int):
 Coordination number for the initial site. c2 (Int):
 Coordination number for the final site. Returns: (Float):
 The relative probability of this jump occurring. """

        if self.site_energies:
            site_delta_E = self.site_energies[ l2 ] - self.site_energies[ l1 ]
        else:
            site_delta_E = 0.0
        if self.nn_energy:
            delta_nn = c2 - c1 - 1 # -1 because the hopping ion is not counted in the final site occupation number
            site_delta_E += delta_nn * self.nn_energy
        return metropolis( site_delta_E )