bitfinex api v2 error, invalid key

I am trying to make a basic authenticated api call to their new v2 api and getting an invalid api key error returned.

I reissued the api key just to verify, same error.

from time import time
import urllib.request
import urllib.parse
import hashlib
import hmac

APIkey = b'myapikeyyouarenotsupposedtosee'
secret = b'myceeeeecretkeyyyy'

url = 'https://api.bitfinex.com/v2/auth/r/wallets'

payload = {
    #'request':'/auth/r/wallets',
    'nonce': int(time() * 1000),
}

paybytes = urllib.parse.urlencode(payload).encode('utf8')
print(paybytes)

sign = hmac.new(secret, paybytes, hashlib.sha512).hexdigest()
print(sign)

headers = {
    'Key': APIkey,
    'Sign': sign
}

req = urllib.request.Request(url, headers=headers, data=paybytes)
with urllib.request.urlopen(req) as response:
    the_page = response.read()
    print(the_page)

How do I make an authenticated api call to the new v2 API for bitfinex?