code: def getitem(source, index):
      
      if isinstance(index, builtins.slice):
          return slice.raw(source, index.start, index.stop, index.step)
      if isinstance(index, int):
          return item.raw(source, index)
      raise TypeError("Not a valid index (int or slice)")
docs: Forward one or several items from an asynchronous sequence.
  
      The argument can either be a slice or an integer.
      See the slice and item operators for more information.