code: func (c *Ledger) QueryBlock(reqCtx reqContext.Context, blockNumber uint64, targets []fab.ProposalProcessor, verifier ResponseVerifier) ([]*common.Block, error) {
  
  	cir := createBlockByNumberInvokeRequest(c.chName, blockNumber)
  	tprs, errs := queryChaincode(reqCtx, c.chName, cir, targets, verifier)
  
  	responses, errors := getConfigBlocks(tprs)
  	errs = multi.Append(errs, errors)
  	return responses, errs
  }
docs: // QueryBlock queries the ledger for Block by block number.
  // This query will be made to specified targets.
  // blockNumber: The number which is the ID of the Block.
  // It returns the block.