Here's a simple example of how one can use the abc (Abstract Base Class) library in Python3 as an alternative to "raise NotImplementedError" when creating abstract classes

abstract_base_classes.py

#!/usr/bin/env python3

import abc

class Task(abc.ABC):
    @abc.abstractmethod
    def do(self):
        pass

    @abc.abstractmethod
    def rollback(self):
        pass

class CoolTask(Task):
    def __init__(self, name):
        self.name = name

    def do(self, description):
        print(f'{self.name}: doing task')
        print(f'description: {description}')

    def rollback(self, description):
        print(f'{self.name}: rolling back task')
        print(f'description: {description}')

class YellTask(Task):
    def __init__(self, name):
        self.name = name

    def do(self):
        print(f'{self.name.upper()}: DOING TASK')

    def rollback(self):
        print(f'{self.name.upper()}: ROLLING BACK TASK')


t = CoolTask("my cool task")
t.do("prints what I'm doing")
t.rollback("prints what I'm rolling back")

y = YellTask("my yelling task")
y.do()
y.rollback()