code: def find_version_by_string_lib(
      line, version_token="__version__"
  ):  # type: (str,str)->Optional[str]
      
      if not line:
          return None
      simplified_line = simplify_line(line)
      version = None
      if simplified_line.strip().startswith(version_token):
          if '"' not in simplified_line:
              pass
              # logger.debug("Weird version string, no double quote : " + unicode((full_path, line, simplified_line)))
          else:
              if "=" in simplified_line:
                  post_equals = simplified_line.split("=")[1]
  
                  if post_equals.startswith('"'):
                      parts = post_equals.split('"')
                      version = parts[0]
                  if not version:
                      version = None
      return version
docs: No regex parsing. Or at least, mostly, not regex.