def test_2(): assert kelvins(-50) == 223.15
def test_8(): assert kelvins(1000) == 1273.15
def test_1(): assert kelvins(-273.15) == 0
def test_7(): assert kelvins(100) == 373.15
def test_6(): assert kelvins(37) == 310.15
def test_5(): assert kelvins(21) == 294.15
def test_4(): assert kelvins(0) == 273.15
def test_3(): assert kelvins(-10) == 263.15