'sessionmaker' object has no attribute 'query'

Pyramid - load_base_data.py Attribute Errror

/Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/venv/bin/python "/Users/michael/Library/Application Support/JetBrains/Toolbox/apps/PyCharm-P/ch-0/193.6494.30/PyCharm.app/Contents/plugins/python/helpers/pycharm/pycharm_load_entry_point.py" /Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/development.ini
Connecting to DB at: sqlite:////Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/billtracker/db/bill_tracker.sqlite
Loading starter data...
Traceback (most recent call last):
  File "/Users/michael/Library/Application Support/JetBrains/Toolbox/apps/PyCharm-P/ch-0/193.6494.30/PyCharm.app/Contents/plugins/python/helpers/pycharm/pycharm_load_entry_point.py", line 12, in <module>
    sys.exit(f())
  File "/Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/venv/lib/python3.7/site-packages/pyramid-1.10.4-py3.7.egg/pyramid/scripts/pserve.py", line 34, in main
    return command.run()
  File "/Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/venv/lib/python3.7/site-packages/pyramid-1.10.4-py3.7.egg/pyramid/scripts/pserve.py", line 275, in run
    app = loader.get_wsgi_app(app_name, config_vars)
  File "/Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/venv/lib/python3.7/site-packages/plaster_pastedeploy-0.7-py3.7.egg/plaster_pastedeploy/__init__.py", line 129, in get_wsgi_app
    global_conf=defaults,
  File "/Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/venv/lib/python3.7/site-packages/PasteDeploy-2.1.0-py3.7.egg/paste/deploy/loadwsgi.py", line 253, in loadapp
    return loadobj(APP, uri, name=name, **kw)
  File "/Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/venv/lib/python3.7/site-packages/PasteDeploy-2.1.0-py3.7.egg/paste/deploy/loadwsgi.py", line 278, in loadobj
    return context.create()
  File "/Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/venv/lib/python3.7/site-packages/PasteDeploy-2.1.0-py3.7.egg/paste/deploy/loadwsgi.py", line 715, in create
    return self.object_type.invoke(self)
  File "/Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/venv/lib/python3.7/site-packages/PasteDeploy-2.1.0-py3.7.egg/paste/deploy/loadwsgi.py", line 152, in invoke
    return fix_call(context.object, context.global_conf, **context.local_conf)
  File "/Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/venv/lib/python3.7/site-packages/PasteDeploy-2.1.0-py3.7.egg/paste/deploy/util.py", line 55, in fix_call
    val = callable(*args, **kw)
  File "/Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/billtracker/__init__.py", line 17, in main
    init_db()
  File "/Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/billtracker/__init__.py", line 30, in init_db
    load_base_data.load_starter_data()
  File "/Users/michael/Developer/TalkPython/100-days-of-web/100-days-of-web-with-python/037-pyramid/billtracker/billtracker/bin/load_base_data.py", line 17, in load_starter_data
    if session.query(Bill).count() > 0:
AttributeError: 'sessionmaker' object has no attribute 'query'

Process finished with exit code 1