def test_oxidation_state_not_exist(): assert oxidation_state("Os") == 0
def test_oxidation_state(): assert oxidation_state("H") == 1
def test_oxidation_state_bi(): assert oxidation_state("Bi") == 3
def _oxidation_state(self, element): try: return self._overwritten_oxi_states[element] except KeyError: return oxidation_state(element)