code: func (ngram *NGramIndex) countNgrams(inputNgrams []uint32) map[TokenID]int {
  	counters := make(map[TokenID]int)
  	for _, ngramHash := range inputNgrams {
  		ngram.RLock()
  		for tok := range ngram.index[ngramHash] {
  			counters[tok]++
  		}
  		ngram.RUnlock()
  	}
  	return counters
  }
docs: // countNgrams maps matched tokens to the number of ngrams, shared with input string