code: func (api *PrivateDebugAPI) GetModifiedAccountsByNumber(startNum uint64, endNum *uint64) ([]common.Address, error) {
  	var startBlock, endBlock *types.Block
  
  	startBlock = api.eth.blockchain.GetBlockByNumber(startNum)
  	if startBlock == nil {
  		return nil, fmt.Errorf("start block %x not found", startNum)
  	}
  
  	if endNum == nil {
  		endBlock = startBlock
  		startBlock = api.eth.blockchain.GetBlockByHash(startBlock.ParentHash())
  		if startBlock == nil {
  			return nil, fmt.Errorf("block %x has no parent", endBlock.Number())
  		}
  	} else {
  		endBlock = api.eth.blockchain.GetBlockByNumber(*endNum)
  		if endBlock == nil {
  			return nil, fmt.Errorf("end block %d not found", *endNum)
  		}
  	}
  	return api.getModifiedAccounts(startBlock, endBlock)
  }
docs: // GetModifiedAccountsByNumber returns all accounts that have changed between the
  // two blocks specified. A change is defined as a difference in nonce, balance,
  // code hash, or storage hash.
  //
  // With one parameter, returns the list of accounts modified in the specified block.