raise NotImplemented —> raise NotImplementedError

Created by: cclauss

flake8 . --count --exit-zero --max-complexity=10 --statistics

./solutions/object_oriented_design/call_center/call_center.py:69:9:
F901 'raise NotImplemented' should be 'raise NotImplementedError'

https://docs.python.org/3/library/exceptions.html#NotImplementedError