AttributeError in example/push_transaction about eospy HOT 6 CLOSED

import eospy.cleos
import eospy.keys
from eospy.types import Abi, Action
from eospy.utils import parse_key_file
import os
import pytz
import json


ce = eospy.cleos.Cleos(url='https://eos.greymass.com:443')

# use a string or EOSKey for push_transaction
# # use EOSKey:
key = eospy.keys.EOSKey('5KQwrPbwdL6PhXujxW37FSSQZ1JiwsST4cqQzDeyXtP79zkvFD3')


script_dir = os.path.dirname(os.path.realpath(__file__))


########################################
# VOTE
########################################

abi_file = os.path.join(script_dir, 'eosio.system.abi')

with open(abi_file) as rf:
    abi_json = json.load(rf)
    sys_abi = Abi(abi_json)

    # wait to send transaction
    import time
    print('Pushing a vote after 2 seconds using abi file: {}'.format(abi_file))
    time.sleep(2)

    vote_payload = {
        "account": "eosio",
        "name": "voteproducer",
        "authorization": [{
            "actor": "eosaccount",
            "permission": "active",
        }],
    }

    vote_params = {
        "voter": "eosaccount",  # sender
        "proxy": "eosproxy",  # proxy
        "producers": []  # producers
    }

    # Voting Converting payload to binary
    data = ce.abi_json_to_bin(vote_payload['account'], vote_payload['name'], vote_params)
    print(data)


############################### Problem ######################################

    vote_data = sys_abi.json_to_bin(vote_payload['name'], vote_params)

############################### Problem   ######################################

    # Inserting payload binary form as "data" field in original payload
    vote_payload['data'] = vote_data
    print(vote_payload)
    # final transaction formed
    trx = {"actions": [vote_payload]}

    # resp = ce.push_transaction(trx, eospy.keys.EOSKey(key), broadcast=True)
    print('------------------------------------------------')
    print(resp)
    print('------------------------------------------------')

Traceback (most recent call last):
  File "p.py", line 57, in <module>
    vote_data = sys_abi.json_to_bin(vote_payload['name'], vote_params)
AttributeError: 'Abi' object has no attribute 'json_to_bin'

from eospy.types import Abi, Action
import json

abi_file = "/home/deck/Documents/git/eosnewyork/eospy/examples/eosio.system.abi"

with open(abi_file) as rf:
    abi_json = json.load(rf)
    sys_abi = Abi(abi_json)

    vote_payload = {
        "account": "eosio",
        "name": "voteproducer",
        "authorization": [{
            "actor": "eosaccount",
            "permission": "active",
        }],
    }

    vote_params = {
        "voter": "eosaccount",  # sender
        "proxy": "eosproxy",  # proxy
        "producers": []  # producers
    }

    data = sys_abi.json_to_bin(vote_payload['name'], vote_params)
    print(data)