class_docstr: Read notebook cells from Sphinx Gallery scripts (#80)
class_docstr_tok: ["Read","notebook","cells","from","Sphinx","Gallery","scripts","(","#","80",")"]
docstr: Does this line starts a new markdown cell?
  Then, return the cell marker
docstr_tok: ["Does","this","line","starts","a","new","markdown","cell","?","Then",",","return","the","cell","marker"]
code: def start_of_new_markdown_cell(self, line):
      """Does this line starts a new markdown cell?
      Then, return the cell marker"""
      for empty_markdown_cell in ['""', "''"]:
          if line == empty_markdown_cell:
              return empty_markdown_cell
  
      for triple_quote in ['"""', "'''"]:
          if line.startswith(triple_quote):
              return triple_quote
  
      if self.twenty_hash.match(line):
          return line
  
      return None
  
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 2 for calling the SphinxGalleryScriptCellReader obj's underlying member method code with example usage: obj.start_of_new_markdown_cell(line) and returns: None, line, empty_markdown_cell, triple_quote