Sadly I'm not able to test the code at the moment as I'm writing from my mobile, but it should look like this:

    from steem import Steem
    from steem.blockchain import Blockchain
    from steem.amount import Amount
    from steem.account import Account
    import json
    import datetime
    
    def converter(object_):
        if isinstance(object_, datetime.datetime):
            return object_.__str__()
    
    def run():
        steem = Steem()
        blockchain = Blockchain()
        stream = blockchain.stream(filter_by=["transfer"])
    
        username = "amosbastian"
    
        account = Account(username)
    
        reward_fund = steem.get_reward_fund()
        reward_balance = Amount(reward_fund["reward_balance"]).amount
        recent_claims = float(reward_fund["recent_claims"])
        reward_share = reward_balance / recent_claims
        base = Amount(steem.get_current_median_history_price()["base"]).amount
    
        while True:
            try:
                for transfer in stream:
                    if transfer["to"] == username:
                        url, permlink = transfer["memo"].split("@")
                        if "https://steemit.com/" in url:
                            vests = account.get_balances()['available']['VESTS']
                            vp = vests * 0.02
    
                            value = vp * base * reward_share
                            
                            p = float(str(transfer["amount"]).replace(" STEEM", "")) * base
                            
                            if value < p:
                                steem.vote(f"@{permlink}", 100)
                                refund = p - value
                                steem.transfer(transfer['from'], amount=refund, asset="SBD", account=username)
                            else:
                                steem.vote(f"@{permlink}", 100 * (p/value))
            except Exception as error:
                print(repr(error))
                continue