Function build_token_unshield_with_shielded_fee_transition 

pub fn build_token_unshield_with_shielded_fee_transition<P: OrchardProver>(
    token_id: Identifier,
    data_contract_id: Identifier,
    token_contract_position: TokenContractPosition,
    spender: TokenPoolSpender<'_>,
    recipient_id: Identifier,
    amount: TokenAmount,
    memo: [u8; 36],
    fee_payer: ShieldedFeePayer<'_>,
    prover: &P,
    platform_version: &PlatformVersion,
) -> Result<(StateTransition, Credits), ProtocolError>

Builds a TokenUnshieldWithShieldedFee: amount of the token leaves the token’s shielded pool into recipient_id’s balance, the fee is paid out of the credit shielded pool. Returns the transition and the fee paid.