python3 encoding

[rgusso]

python3 -V
Python 3.7.3

from pyvantagepro import VantagePro2
import datetime as d
s = d.datetime.strptime('2020-01-16 19:00:00','%Y-%m-%d %H:%M:%S')
f = d.datetime.strptime('2020-01-16 19:30:00','%Y-%m-%d %H:%M:%S')
device = VantagePro2.from_url('tcp:192.168.0.106:22222')
data = device.get_archives(s,f)

File "/usr/local/lib/python3.7/dist-packages/pyvantagepro/parser.py", line 66, in checksum
    for byte in array(str('B'), bytes(self.data)): 
TypeError: string argument without an encoding

is this a problem with python3?

UPDATE
Working fine in python2.7