How to transfer Fungible Assets via Python?

[sellmon]

Discord user ID

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Describe your question in detail.

Hi, I need help with creating a transaction (tx) for transferring FA. Here's the code:

async def send_fa(sender_key="0x..., receiver="0x...", amount=100):
    sender = Account.load_key(str(sender_key))

    try:
        logger.info("Send USDT FA")

        payload = EntryFunction.natural(
            "0x1::aptos_account",
            "transfer_fungible_assets",
            [],
            [
                TransactionArgument(sender, Serializer.struct),
                TransactionArgument(StructTag.from_str("0x1::object::Object<0x357b0b74bc833e95a115ad22604854d6b0fca151cecd94111770e5d6ffc9dc2b>")),
                TransactionArgument(AccountAddress.from_str(receiver), Serializer.struct),
                TransactionArgument(amount, Serializer.u64),
            ],
        )

        transaction = await rest_client.create_bcs_signed_transaction(sender, TransactionPayload(payload))
        txn_hash = await rest_client.submit_bcs_transaction(transaction)
        await rest_client.wait_for_transaction(txn_hash)

        return txn_hash

I've tried different variants, but I can’t understand how to do it via Python. In TypeScript, everything works fine, but I need it in Python for my case.

What error, if any, are you getting?

No response

What have you tried or looked at? Or how can we reproduce the error?

No response

Which operating system are you using?

macOS

Which SDK or tool are you using? (if any)

Python SDK

Describe your environment or tooling in detail

No response

[0x-j]

what error are you running into? we have some python sdk example in https://github.com/aptos-labs/aptos-python-sdk/tree/main/examples

[sellmon]

I tried this one

async def transfer_fungible_assets(sender_key=WALLET, amount=100):
    sender = Account.load_key(str(sender_key))

    payload = TransactionPayload(
        EntryFunction.natural(
            "0x1::aptos_account",
            "transfer_fungible_assets",
            [],
            [
                TransactionArgument(AccountAddress.from_str("0x357b0b74bc833e95a115ad22604854d6b0fca151cecd94111770e5d6ffc9dc2b"), Serializer.struct),
                TransactionArgument(AccountAddress.from_str("0x..."), Serializer.struct),
                TransactionArgument(amount, Serializer.u64),
            ],
        )
    )

    transaction = await rest_client.create_bcs_transaction(sender, payload)
    print(transaction)

    simulation = await rest_client.simulate_transaction(transaction, sender)
    logger.debug(f"{(simulation[0].get('payload'),)} Simulation: {simulation[0].get('vm_status')}")
    return simulation

And got this answer:

DEBUG    | ({'function': '0x1::aptos_account::transfer_fungible_assets', 'type_arguments': [], 'arguments': [{'inner': '0x357b0b74bc833e95a115ad22604854d6b0fca151cecd94111770e5d6ffc9dc2b'}, '0x...', '100'], 'type': 'entry_function_payload'},) Simulation: Move abort in 0x1::fungible_asset: EINSUFFICIENT_BALANCE(0x10004): Insufficient balance to withdraw or transfer.

RawTransaction:
    sender: 0x...
    sequence_number: 790
    payload: 0x1::aptos_account::transfer_fungible_assets::<[]>([b'5{\x0bt\xbc\x83>\x95\xa1\x15\xad"`HT\xd6\xb0\xfc\xa1Q\xce\xcd\x94\x11\x17p\xe5\xd6\xff\xc9\xdc+', b'@\xad\x87\xd3\xa1n\x88\xf1\x97\xe5\xa2\x8f\x87U\xb7f\xe1\xceS\x0e\xaf\xdb\xf4;\x97\x18\xdf\xa4"\xac\xba\xab', b'd\x00\x00\x00\x00\x00\x00\x00'])
    max_gas_amount: 100
    gas_unit_price: 100
    expiration_timestamps_secs: 1741634619
    chain_id: 1

I have enough balance on address and different gas didn't help

[sellmon]

The next day, I solved the problem in 2 minutes—just looked at the payload for sending a transaction via the wallet and realized I was using the wrong function.

I should have used 0x1::primary_fungible_store::transfer instead of 0x1::aptos_account::transfer_fungible_assets.

So, the payload looks like this in case it's useful to anyone:

payload = TransactionPayload(
    EntryFunction.natural(
        "0x1::primary_fungible_store",
        "transfer",
        [TypeTag(StructTag.from_str("0x1::fungible_asset::Metadata"))],
        [
            TransactionArgument(AccountAddress.from_str("0x...fa_address"), Serializer.struct),
            TransactionArgument(AccountAddress.from_str("0x...receiver"), Serializer.struct),
            TransactionArgument(amount, Serializer.u64),
        ],
    )
)