old_contents: import os
  from moban.utils import HashStore
  
  
  class TestHashStore:
      def tearDown(self):
          os.unlink('.moban.hashes')
  
      def test_simple_use_case(self):
          hs = HashStore()
          flag = hs.is_file_changed('test.out', 'test content')
          assert flag is True
          hs.close()
  
      def test_simple_use_case_1(self):
          hs = HashStore()
          flag = hs.is_file_changed('test.out', 'test content')
          hs.close()
          hs2 = HashStore()
          flag = hs2.is_file_changed('test.out', 'test content')
          assert flag is False
          hs2.close()
  
new_contents: import os
  from moban.utils import HashStore
  
  
  class TestHashStore:
      def setUp(self):
          self.fixture = ('test.out', 'test content'.encode('utf-8'))
  
      def tearDown(self):
          os.unlink('.moban.hashes')
  
      def test_simple_use_case(self):
          hs = HashStore()
          flag = hs.is_file_changed(*self.fixture)
          assert flag is True
          hs.close()
  
      def test_simple_use_case_1(self):
          hs = HashStore()
          flag = hs.is_file_changed(*self.fixture)
          hs.close()
          hs2 = HashStore()
          flag = hs2.is_file_changed(*self.fixture)
          assert flag is False
          hs2.close()
  
subject: fix broken test