new_contents: from thermopy.units import Pressure, Temperature
  from nose.tools import assert_equals
  
  
  def test_temperature():
      assert_equals(Temperature(273.15).unit('K'), Temperature(0).unit('C'))
  
  
  def test_pressure():
      assert_equals(Pressure(760).unit('torr'), Pressure(1).unit('atm'))
  
subject: Add tests for units