code: def get_handler_class(ext):
      
  
      if ext in _extensions_map:
          format = _extensions_map[ext]
      else:
          raise ValueError("Unknown format for %s extension." % ext)
  
      if format in _handler_map:
          hc = _handler_map[format]
          return hc
      else:
          matches = difflib.get_close_matches(format, _handler_map.keys())
          raise ValueError("Unknown Handler for format %s, close matches: %s"
                           % (format, str(matches)))
docs: Get the IOHandler that can handle the extension *ext*.