code: def _parse_common(tag):
      
      if "modifiers" in tag.attrib:
          modifiers = re.split(",\s*", tag.attrib["modifiers"].strip())
          if "" in modifiers:
              modifiers.remove("")
      else:
          modifiers = None
  
      if "name" in tag.attrib:
          name = tag.attrib["name"]
      if "type" in tag.attrib:
          dtype = tag.attrib["type"]
      else:
          dtype = None
      if "kind" in tag.attrib:
          kind = tag.attrib["kind"]
      else:
          kind = None
  
      return (name, modifiers, dtype, kind)
docs: Returns a tuple of (name, modifiers, dtype, kind)
      for the specified tag. Any missing attributes will have values of None.