new_contents: import unittest
  from lru import LRU
  
  SIZES = [1, 2, 10, 1000]
  
  class TestLRU(unittest.TestCase):
  
      def setUp(self):
          pass
  
      def test_empty(self):
          l = LRU(1)
          self.assertEquals([], l.keys())
  
      def test_add_within_size(self):
          for size in SIZES:
  	    l = LRU(size)
              for i in xrange(size):
                  l[i] = str(i)
              self.assertEquals(range(size-1,-1,-1), l.keys())
  
      def test_delete_multiple_within_size(self):
          for size in SIZES:
              l = LRU(size)
              for i in xrange(size):
                  l[i] = str(i)
              for i in xrange(0,size,2):
                  del l[i]
              self.assertEquals(range(size-1,0,-2), l.keys())
              for i in range(0,size,2):
         	        with self.assertRaises(KeyError):
                      l[i]
  
      def test_add_multiple(self):
          for size in SIZES:
              l = LRU(size)
              for i in xrange(size):
                  l[i] = str(i)
              l[size] = size
              self.assertEquals(range(size,0,-1), l.keys())
  
      def test_access_within_size(self):
          for size in SIZES:
              l = LRU(size)
              for i in xrange(size):
                  l[i] = str(i)
              for i in xrange(size):
                  self.assertEquals(l[i], str(i))
  
      def test_access(self):
          for size in SIZES:
              l = LRU(size)
              n = size * 2
              for i in xrange(n):
                  l[i] = str(i)
              self.assertEquals(range(n-1,size-1,-1), l.keys())
              for i in xrange(size, n):
                  self.assertEquals(l[i], str(i))
  
  if __name__ == '__main__':
      unittest.main()
  
subject: Add basic tests