docstr: Can an old notebook be opened and converted to the current version
  while remembering the original version of the notebook?
docstr_tok: ["Can","an","old","notebook","be","opened","and","converted","to","the","current","version","while","remembering","the","original","version","of","the","notebook","?"]
code: def test_open_current(self):
      """Can an old notebook be opened and converted to the current version
      while remembering the original version of the notebook?"""
  
      # Open a version 2 notebook and attempt to upgrade it to the current version
      # while remembering it's version information.
      with self.fopen("test2.ipynb", "r") as f:
          nb = read(f)
      (original_major, original_minor) = get_version(nb)
      nb = convert(nb, current_nbformat)
  
      # Check if upgrade was successful.
      (major, minor) = get_version(nb)
      self.assertEqual(major, current_nbformat)
  
      # Check if the original major revision was remembered.
      self.assertEqual(original_major, 2)
  
file_path: nbformat/tests/test_convert.py
imports: from __future__ import annotations
  from nbformat import current_nbformat
  from nbformat.converter import convert
  from nbformat.reader import get_version, read
  from nbformat.validator import ValidationError, isvalid, validate
  from .base import TestsBase
label_desc: Use image node_id 5 for calling the TestConvert obj's underlying member method code with example usage: obj.test_open_current() without return types