old_contents: # coding: utf-8
  from collections import OrderedDict
  
  
  def _convert_sheets_to_lists(content):
      cols = OrderedDict()
      if not content or len(content) is 0:
          return [], None
      if isinstance(content[0], list):
          cols.update(OrderedDict.fromkeys(content[0]))
      for row in content:
          if isinstance(row, dict):
              cols.update(OrderedDict.fromkeys(row.keys()))
      cols = cols.keys()
      out_content = []
      _valid = False
      for row in content:
          out_row = []
          for col in cols:
              _val = row.get(col, '')
              if _val is None:
                  _val = ''
              out_row.append(_val)
          if len(out_row) > 0:
              _valid = True
          out_content.append(out_row)
      return cols, out_content if _valid else None
  
  
  def ss_structure_to_mdtable(content):
      """
      receives a dict or OrderedDict with arrays of arrays representing
      a spreadsheet, and returns a markdown document with tables
      """
      import tabulate
      out_sheets = OrderedDict()
      output = []
  
      def cell_to_str(cell):
          return '' if cell is None else str(cell)
  
      for (sheet_name, contents) in content.items():
          out_sheets[sheet_name] = output
          (headers, content) = _convert_sheets_to_lists(contents)
          if content:
              output.append('#{}'.format(sheet_name))
              output.append(tabulate.tabulate(content,
                                              headers=headers,
                                              tablefmt="orgtbl"))
      return '\n\n'.join(output)
  
new_contents: # coding: utf-8
  from collections import OrderedDict
  
  
  def _convert_sheets_to_lists(content):
      cols = OrderedDict()
      if not content or len(content) == 0:
          return [], None
      if isinstance(content[0], list):
          cols.update(OrderedDict.fromkeys(content[0]))
      for row in content:
          if isinstance(row, dict):
              cols.update(OrderedDict.fromkeys(row.keys()))
      cols = cols.keys()
      out_content = []
      _valid = False
      for row in content:
          out_row = []
          for col in cols:
              _val = row.get(col, '')
              if _val is None:
                  _val = ''
              out_row.append(_val)
          if len(out_row) > 0:
              _valid = True
          out_content.append(out_row)
      return cols, out_content if _valid else None
  
  
  def ss_structure_to_mdtable(content):
      """
      receives a dict or OrderedDict with arrays of arrays representing
      a spreadsheet, and returns a markdown document with tables
      """
      import tabulate
      out_sheets = OrderedDict()
      output = []
  
      def cell_to_str(cell):
          return '' if cell is None else str(cell)
  
      for (sheet_name, contents) in content.items():
          out_sheets[sheet_name] = output
          (headers, content) = _convert_sheets_to_lists(contents)
          if content:
              output.append('#{}'.format(sheet_name))
              output.append(tabulate.tabulate(content,
                                              headers=headers,
                                              tablefmt="orgtbl"))
      return '\n\n'.join(output)
  
subject: Resolve `SyntaxWarning: "is" with a literal`