code: def test_notebook_blank_lines(
      script="""# +
  # This is a comment
  # followed by two variables
  a = 3
  
  b = 4
  # -
  
  # New cell is a variable
  c = 5
  
  
  # +
  # Now we have two functions
  def f(x):
      return x + x
  
  
  def g(x):
      return x + x + x
  
  
  # -
  
  
  # A commented block that is two lines away
  # from previous cell
  
  # A function again
  def h(x):
      return x + 1
  
  
  # variable
  d = 6
  """,
  ):
      notebook = jupytext.reads(script, "py")
      assert len(notebook.cells) >= 6
      for cell in notebook.cells:
          lines = cell.source.splitlines()
          if len(lines) != 1:
              assert lines[0], cell.source
              assert lines[-1], cell.source
  
      script2 = jupytext.writes(notebook, "py")
  
      compare(script2, script)
  
imports: import pytest
  from nbformat.v4.nbbase import new_code_cell, new_markdown_cell, new_notebook, new_raw_cell
  import jupytext
  from jupytext.compare import compare, compare_notebooks
label_desc: Use image node_id 24 for calling a global function with example usage: test_notebook_blank_lines(script) without return types