code: def consume(iterator: Iterator[T], n: Optional[int] = None) -> None:
      
      # Use functions that consume iterators at C speed.
      if n is None:
          # feed the entire iterator into a zero-length deque
          collections.deque(iterator, maxlen=0)
      else:
          # advance to the empty slice starting at position n
          next(itertools.islice(iterator, n, n), None)
docs: Advance the iterator n-steps ahead. If n is None, consume entirely.