createAccountHolder function, and such a system could be for recording transactions of a particular category such as cards or securities. An accounting system represented by an account holder can have multiple ledgers. Each ledger is created using the createLedger function, and represents an account which is created using the createAccount function.createAccount function. Transactions can be posted using the postEntry function, and they can retrieved using the getEntry function which could be very useful in enabling users search for transactions.getAccountStatement function. Before account statements are fetched, applications need to update them using the updateAccountStatement function which sums up account balances in various ledgers that may exist for an account holder representing the user.