old_contents: """
  @brief      test log(time=10s)
  """
  
  import sys
  import os
  import unittest
  
  
  try:
      import src
  except ImportError:
      path = os.path.normpath(
          os.path.abspath(
              os.path.join(
                  os.path.split(__file__)[0],
                  "..",
                  "..")))
      if path not in sys.path:
          sys.path.append(path)
      import src
  
  from src.pyquickhelper.ipythonhelper import read_nb
  from src.pyquickhelper.pycode import get_temp_folder
  from src.pyquickhelper.loghelper import fLOG
  
  
  class TestNotebookRunnerOperation (unittest.TestCase):
  
      def test_notebook_runner_operation(self):
          fLOG(
              __file__,
              self._testMethodName,
              OutputPrint=__name__ == "__main__")
          if sys.version_info[0] == 2:
              # written in Python 3
              return
          temp = get_temp_folder(__file__, "temp_notebook_operation")
  
          nbfile = os.path.join(temp, "..", "data", "simple_example.ipynb")
          nbfile2 = os.path.join(
              temp, "..", "data", "td2a_cenonce_session_4B.ipynb")
          nb1 = read_nb(nbfile, kernel=False)
          n1 = len(nb1)
          nb2 = read_nb(nbfile2, kernel=False)
          n2 = len(nb2)
          add = nb1 + nb2
          nb1.merge_notebook([nb2])
          n3a = len(add)
          n3 = len(nb1)
          if n1 + n2 != n3:
              raise Exception("{0} + {1} != {2}".format(n1, n2, n3))
          if n3a != n3:
              raise Exception("{0} != {1}".format(n3a, n3))
  
          fLOG(n1, n2, n3, n3a)
          outfile = os.path.join(temp, "merge_nb.ipynb")
          nb1.to_json(outfile)
          assert os.path.exists(outfile)
          outfile = os.path.join(temp, "merge_nb_add.ipynb")
          add.to_json(outfile)
          assert os.path.exists(outfile)
  
  
  if __name__ == "__main__":
      unittest.main()
  
new_contents: """
  @brief      test log(time=11s)
  """
  
  import sys
  import os
  import unittest
  
  
  try:
      import src
  except ImportError:
      path = os.path.normpath(
          os.path.abspath(
              os.path.join(
                  os.path.split(__file__)[0],
                  "..",
                  "..")))
      if path not in sys.path:
          sys.path.append(path)
      import src
  
  from src.pyquickhelper.ipythonhelper import read_nb
  from src.pyquickhelper.pycode import get_temp_folder
  from src.pyquickhelper.loghelper import fLOG
  
  
  class TestNotebookRunnerOperation (unittest.TestCase):
  
      def test_notebook_runner_operation(self):
          fLOG(
              __file__,
              self._testMethodName,
              OutputPrint=__name__ == "__main__")
          if sys.version_info[0] == 2:
              # written in Python 3
              return
          temp = get_temp_folder(__file__, "temp_notebook_operation")
  
          nbfile = os.path.join(temp, "..", "data", "simple_example.ipynb")
          nbfile2 = os.path.join(
              temp, "..", "data", "td2a_cenonce_session_4B.ipynb")
          nb1 = read_nb(nbfile, kernel=False)
          n1 = len(nb1)
          nb2 = read_nb(nbfile2, kernel=False)
          n2 = len(nb2)
          add = nb1 + nb2
          nb1.merge_notebook([nb2])
          n3a = len(add)
          n3 = len(nb1)
          if n1 + n2 != n3:
              raise Exception("{0} + {1} != {2}".format(n1, n2, n3))
          if n3a != n3:
              raise Exception("{0} != {1}".format(n3a, n3))
  
          fLOG(n1, n2, n3, n3a)
          outfile = os.path.join(temp, "merge_nb.ipynb")
          nb1.to_json(outfile)
          assert os.path.exists(outfile)
          outfile = os.path.join(temp, "merge_nb_add.ipynb")
          add.to_json(outfile)
          assert os.path.exists(outfile)
  
  
  if __name__ == "__main__":
      unittest.main()
  
subject: test for travis 7.10.2