I am developing my Bitcoin wallet (testnet) on Python using the Cryptos library. I started integrating support for deterministic wallets and mnemonic words. Now I have enabled users to generate addresses, addresses and private keys I store in an encrypted sqlite3 database file, addresses and public keys in a simple sqlite3 file.
How can an algorithm for generating a transaction with multiple inputs be effectively implemented? The library has built-in functions such as unspent (show UTXO for the address). I understand that I will have to loop through utxo and then select private keys for signing, but is there a more efficient way?
