code: func (mp *TxPool) TxHashes() []*chainhash.Hash {
  	mp.mtx.RLock()
  	hashes := make([]*chainhash.Hash, len(mp.pool))
  	i := 0
  	for hash := range mp.pool {
  		hashCopy := hash
  		hashes[i] = &hashCopy
  		i++
  	}
  	mp.mtx.RUnlock()
  
  	return hashes
  }
docs: // TxHashes returns a slice of hashes for all of the transactions in the memory
  // pool.
  //
  // This function is safe for concurrent access.