code: func (b *RWSetBuilder) AddToHashedReadSet(ns string, coll string, key string, version *version.Height) {
  	kvReadHash := newPvtKVReadHash(key, version)
  	b.getOrCreateCollHashedRwBuilder(ns, coll).readMap[key] = kvReadHash
  }
docs: // AddToHashedReadSet adds a key and corresponding version to the hashed read-set