Glossary

• abc.ABC: A base class for defining abstract behavior.
• bool: The Python type for True or False.
• closure: A function that remembers values from the surrounding scope.
• comprehension: A compact way to build a list, set, or dict.
• concrete type: A specific known type such as int or Student.
• dataclass: A class decorator for simple data-holding classes.
• duck typing: The idea that an object is usable if it behaves correctly.
• generator: A lazy iterable that produces values on demand.
• higher-order function: A function that takes or returns a function.
• inference: The process of working out a type from code and usage.
• iterator: An object that produces values one at a time.
• lambda: A small anonymous function.
• polymorphism: One piece of code working with many types.
• protocol: A description of shared behavior, often using typing.Protocol.
• recursion: A function solving a problem by calling itself.
• type hint: Optional syntax that describes expected types.
• type safety: Avoiding invalid operations on the wrong kind of value.
• user-defined type: A type created by the programmer with class, Enum, or dataclass.