substring not found

[PCswanson]

Running on a raspberry pi, getting the following error when running the sample code from Readme

Traceback (most recent call last):
File "greenhouse pump rest.py", line 4, in
greenhouse = wemo.switch('192.168.86.101')
File "/usr/local/lib/python3.7/dist-packages/wemo/init.py", line 26, in init
self.status: str = self.getStatus()
File "/usr/local/lib/python3.7/dist-packages/wemo/init.py", line 48, in getStatus
return int(self.tagger(rsp, 'BinaryState'))
File "/usr/local/lib/python3.7/dist-packages/wemo/init.py", line 64, in tagger
beg: int = txt.index(f'<{tag}>')
ValueError: substring not found

Any suggestions?