How to get the a block's hash given its number to then feed to filter?

Question

I'm not sure if the first function is getting the hash for the block number given or something else. But the second function doesn't want to accept the parameter.

last_block_hash = web3.eth.get_block(1000)["hash"].hex()
eventFilter = web3.eth.filter(
        "fromBlock" => last_block_hash,
        "topics" => [event_signature_hash]
    )

invalid argument 0: hex number with leading zero digits

Answer 1

The fromBlock should be a block number, not a block hash, so it have to be like that:

eventFilter = web3.eth.filter(
        {"fromBlock": 1000,
        "topics": [event_signature_hash]}
    )

And you have a syntax error by mixing Python and JavaScript, Python use : not => to separate value

last_block_number = 1000
eventFilter = web3.eth.filter(
        {"fromBlock": last_block_number,
        "topics": [event_signature_hash]}
    )