code: def last_two_lines_blank(source):
      """Are the two last lines blank, and not the third last one?"""
      if len(source) < 3:
          return False
      return (
          not _BLANK_LINE.match(source[-3])
          and _BLANK_LINE.match(source[-2])
          and _BLANK_LINE.match(source[-1])
      )
  
imports: import re
  import warnings
  from copy import copy
  from nbformat.v4.nbbase import new_code_cell, new_markdown_cell, new_raw_cell
  from packaging.version import parse
  from .doxygen import doxygen_to_markdown
  from .languages import _SCRIPT_EXTENSIONS
  from .cell_metadata import is_active, is_json_metadata, rmd_options_to_metadata, text_to_metadata
  from .languages import _JUPYTER_LANGUAGES_LOWER_AND_UPPER
  from .magics import is_magic, need_explicit_marker, uncomment_magic, unescape_code_start
  from .pep8 import pep8_lines_between_cells
  from .stringparser import StringParser
label_desc: Use image node_id 5 for calling a global function with example usage: last_two_lines_blank(source) and returns: unknown, False