def METHOD_NAME(self):
    pairs = self.system.cell_system.get_pairs(1.5)
    epairs = self.expected_pairs(self.system.periodicity)
    self.assertSetEqual(set(pairs), set(epairs))
    pairs_by_type = self.system.cell_system.get_pairs(
        1.5, types=self.types_to_get_pairs)
    epairs_by_type = self.expected_pairs_with_types(
        self.system.periodicity)
    self.assertSetEqual(set(pairs_by_type), set(epairs_by_type))