new_contents: import unittest
  
  import pytest
  
  from cupy import cuda
  
  
  class TestDeviceComparison(unittest.TestCase):
  
      def check_eq(self, result, obj1, obj2):
          if result:
              assert obj1 == obj2
              assert obj2 == obj1
              assert not (obj1 != obj2)
              assert not (obj2 != obj1)
          else:
              assert obj1 != obj2
              assert obj2 != obj1
              assert not (obj1 == obj2)
              assert not (obj2 == obj1)
  
      def test_equality(self):
          self.check_eq(True, cuda.Device(0), cuda.Device(0))
          self.check_eq(True, cuda.Device(1), cuda.Device(1))
          self.check_eq(False, cuda.Device(0), cuda.Device(1))
          self.check_eq(False, cuda.Device(0), 0)
          self.check_eq(False, cuda.Device(0), None)
          self.check_eq(False, cuda.Device(0), object())
  
      def test_lt_device(self):
          assert cuda.Device(0) < cuda.Device(1)
          assert not (cuda.Device(0) < cuda.Device(0))
          assert not (cuda.Device(1) < cuda.Device(0))
  
      def test_le_device(self):
          assert cuda.Device(0) <= cuda.Device(1)
          assert cuda.Device(0) <= cuda.Device(0)
          assert not (cuda.Device(1) <= cuda.Device(0))
  
      def test_gt_device(self):
          assert not (cuda.Device(0) > cuda.Device(0))
          assert not (cuda.Device(0) > cuda.Device(0))
          assert cuda.Device(1) > cuda.Device(0)
  
      def test_ge_device(self):
          assert not (cuda.Device(0) >= cuda.Device(1))
          assert cuda.Device(0) >= cuda.Device(0)
          assert cuda.Device(1) >= cuda.Device(0)
  
      def check_comparison_other_type(self, obj1, obj2):
          with pytest.raises(TypeError):
              obj1 < obj2
          with pytest.raises(TypeError):
              obj1 <= obj2
          with pytest.raises(TypeError):
              obj1 > obj2
          with pytest.raises(TypeError):
              obj1 >= obj2
          with pytest.raises(TypeError):
              obj2 < obj1
          with pytest.raises(TypeError):
              obj2 <= obj1
          with pytest.raises(TypeError):
              obj2 > obj1
          with pytest.raises(TypeError):
              obj2 >= obj1
  
      def test_comparison_other_type(self):
          self.check_comparison_other_type(cuda.Device(0), 0)
          self.check_comparison_other_type(cuda.Device(0), 1)
          self.check_comparison_other_type(cuda.Device(1), 0)
          self.check_comparison_other_type(cuda.Device(1), None)
          self.check_comparison_other_type(cuda.Device(1), object())
  
subject: Add device equality tests