How to send ERC721 Token with Python

[xxxxzx]

I want to call safeTransferFrom from a deployed Polygon contract.

safeTransferFrom has 3 arguments:

address from
address to
uint256 tokenId

How do I call this function? I found this tutorial but I’m not sure how to modify it to call a function. Use Python - Infura Docs

Here’s what I have so far:

import os
from dotenv import load_dotenv
from web3 import Web3

load_dotenv()

infura_url = "https://polygon-mainnet.infura.io/v3/API-KEY"
private_key = os.getenv('PRIVATE_KEY')

from_account = 'MY-POLYGON-ADDRESS'
to_account = 'CONTRACT-ADDRESS'

web3 = Web3(Web3.HTTPProvider(infura_url))
nonce = web3.eth.getTransactionCount(from_account)

tx = {
    'type': '0x2',
    'nonce': nonce,
    'from': from_account,
    'to': to_account,
    'value': web3.toWei(0.00, 'ether'),
    'maxFeePerGas': web3.toWei('TOTAL-FEE', 'gwei'),
    'maxPriorityFeePerGas': web3.toWei('PRIORITY-FEE', 'gwei'),
    'chainId': 137
}

gas = web3.eth.estimateGas(tx)
tx['gas'] = gas
signed_tx = web3.eth.account.sign_transaction(tx, private_key)
tx_hash = web3.eth.send_raw_transaction(signed_tx.rawTransaction)
print("Transaction hash: " + str(web3.toHex(tx_hash)))

Thanks!

[traian.vila]

Hey, you’ll pretty much just need to create a contract object and then use this contract.functions method to send a tx and call safeTransferFrom since it’s write function. Something like:

myContract = web3.eth.contract(address=contract_address, abi=contract_abi)
myContract.functions.safeTransferFrom(web3.eth.accounts[1], 0x.., 1234).transact()

Alternatively, if you don’t want to use transact() you can craft the raw tx, sign and send like shown in this example (it’s just a different function to be called):

Web3.py: How to send EIP-1559 transactions (ETH & ERC-20 tokens)

Hello friends! In this tutorial we’re going to take a look at how to use Web3.py to send EIP-1559 transactions, containing either ETH or any verified ERC-20 token. As usual, if you only need the script’s code, feel free to scroll down to the end of the article. Script’s structure The script will be split within two methods, one for sending ETH and another for sending ERC-20 tokens. I recommend only using one method per script run, since the nonce can be erroneously calculated when …

[xxxxzx]

Figured it out, this is also how to call contract functions with web3 using Python. I hope this post helps anyone looking how to do this.

from web3 import Web3

#all instances of brackets denote info you should input (brackets should be removed),
#except for the abi, see below for specific formatting.

#register with infura and get the url at api keys > project name > endpoints > polygon > mainnet
#you need to add a credit card for their free plan and add-on polygon network support when checking out
infura_url = "https://polygon-mainnet.infura.io/v3/[API LINK KEY]"

#use metamask to get private key and put the hex string here in quotes
private_key = "[SENDING ADDRESS PRIVATE KEY]"

#put addresses here in quotes, begins with 0x
from_account = "[SENDING ADDRESS]"
to_account = "[RECEIVING ADDRESS]"

web3 = Web3(Web3.HTTPProvider(infura_url))
nonce = web3.eth.getTransactionCount(from_account)

#replace with id of token you want to send, NO quotes
tokenId = [TOKEN ID]

#contract address here in quotes
contract_address = "[CONTRACT ADDRESS]"

#put entire abi here, go to polygonscan > contract address > contract tab > contract abi
#line should be formatted like this:
#abi = '[{"inputs":[]...'
abi = '[ABI]'

contract = web3.eth.contract(address=contract_address, abi=abi)

tx = contract.functions.safeTransferFrom(from_account, to_account, tokenId).buildTransaction(
	{
		'from': from_account,
		'nonce': nonce,
		'gas': [GAS LIMIT], #gas limit you want i.e. 100000, NO quotes
		'maxFeePerGas': web3.toWei('[TOTAL FEE]', 'gwei'), #total gas fee here (base fee + priority), i.e. web3.toWei('150', 'gwei') can use https://polygonscan.com/gastracker
		'maxPriorityFeePerGas': web3.toWei('[PRIORITY FEE]', 'gwei'), #priority fee here, i.e. web3.toWei('50', 'gwei')
		'chainId': 137 #polygon chain is 137, use https://chainlist.org/ to get your chain id if using a different chain
	}
)

signed_tx = web3.eth.account.sign_transaction(tx, private_key)
tx_hash = web3.eth.send_raw_transaction(signed_tx.rawTransaction)
print("Transaction hash: " + str(web3.toHex(tx_hash)))

[xxxxzx]

Thanks traian, I appreciate it! I happened to figure it out on my own, I posted a complete code snippet of my solution for those looking for more specific instruction.