def test_punct_seq(): assert ws('``,-') == '``,-'
def test_capitalized(): assert ws('Nasa') == 'Xxxx'
def test_space(): assert ws('\n') == '\n'
def test_punct(): assert ws(',') == ','
def test_mix(): assert ws('C3P0') == 'XdXd'
def test_digits(): assert ws('999999999') == 'dddd'
def test_truncate(): assert ws('capitalized') == 'xxxx'