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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 show_halogen(self):
 """Visualize halogen bonds."""

        halogen = self.plcomplex.halogen_bonds
        all_don_x, all_acc_o = [], []
        for h in halogen:
            all_don_x.append(h.don_id)
            all_acc_o.append(h.acc_id)
            cmd.select('tmp_bs', 'id %i & %s' % (h.acc_id, self.protname))
            cmd.select('tmp_lig', 'id %i & %s' % (h.don_id, self.ligname))

            cmd.distance('HalogenBonds', 'tmp_bs', 'tmp_lig')
        if not len(all_acc_o) == 0:
            self.select_by_ids('HalogenAccept', all_acc_o, restrict=self.protname)
            self.select_by_ids('HalogenDonor', all_don_x, restrict=self.ligname)
        if self.object_exists('HalogenBonds'):
            cmd.set('dash_color', 'greencyan', 'HalogenBonds')