old_contents: import unittest
  
  import conftest
  
  
  class MyTest(unittest.TestCase):
    def test_fixture_ran(self):
      assert 'ok' in conftest.V
  
new_contents: import unittest
  
  from . import conftest
  
  
  class MyTest(unittest.TestCase):
    def test_fixture_ran(self):
      assert 'ok' in conftest.V
  
subject: Fix relative import for conftest test on Python 3 (#6941)