Looks like there have been some changes to the Mosquitto v1.0.1 python libraries. So far only hit the one but it was quite a major one. The connect method has been changed. If you try and run your code you will get
Traceback (most recent call last):
File "test.py", line 13, in <module>
TypeError: connect() takes at most 4 arguments (5 given)
In 1.0 the connect function changed from:
def connect(self, hostname="localhost", port=1883, keepalive=60, clean_session=True):
def connect(self, host, port=1883, keepalive=60):
So all it needed was to remove the true flag from the connect statement and then the script worked.