There is no need for additional checks of the caller's key inside the `set_deadline` function because Anchor verifies the `has_one = creator` constraint before executing the function. This ensures that the creator field inside the fund account must match the creator (signer) passed to the function: ``` #[account(mut, has_one = creator)] pub fund: Account<'info, Fund> ``` If they don’t match, the transaction fails. Also, signer verification is included: ``` #[account(mut)] pub creator: Signer<'info>, ``` The creator account must be a signer, meaning the transaction must be signed using the creator's private key.