AttributeError: 'Application' object has no attribute 'sessionID' #1

I am attempting to implement the client.py script as part of a Python3 build. I am getting a repeated error which seems to crash python on occasion. I have tried running this inside/outside of pipenv for containment. I am using FIX Spec 4.2.

It seems the issue is with the following line from the put_order() method.

fix.Session.sendToTarget(trade, self.sessionID)

The error is as follows...

raise AttributeError("'%s' object has no attribute '%s'" % (class_type.__name__, name))
AttributeError: 'Application' object has no attribute 'sessionID'
Segmentation fault: 11

Any thoughts on this? Thanks in advance.