Function default_external_signers 

pub fn default_external_signers(
    mnemonic: String,
    passphrase: Option<String>,
    network: Network,
    account_number: Option<u32>,
) -> Result<ExternalSigners, SdkError>

Creates the default external signers from a mnemonic.

This is a convenience factory method for creating the two signer halves that can be passed to connect_with_signer or SdkBuilder::new_with_signer. Key derivation matches the seed-based connect path: an SDK built either way from the same mnemonic is the same wallet.

Arguments

• mnemonic - BIP39 mnemonic phrase (12 or 24 words)
• passphrase - Optional passphrase for the mnemonic
• network - Network to use (Mainnet or Regtest)
• account_number - Account number in the derivation path. Unset uses the network default: 0 on Regtest, 1 on all other networks.