Describe an abstract class and explain when one might be useful.

Describe an abstract class and explain when one might be useful.
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Answer :

An abstract class is a class that cannot be instantiated but must be inherited. It can contain both implemented methods and abstract methods, which must be implemented in an inheriting class. Thus, it can define common functionality for some methods, a common interface for other methods, and leave more detailed implementation up to the inheriting class.
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