Mastering Advanced Python Concepts

What is a decorator in Python and how is it used?

• A decorator is a function that only returns a string.

• A decorator is a built-in data type in Python.

• A decorator is a type of variable in Python.

• A decorator is a function that wraps another function to modify its behavior.

Explain how to create a simple decorator in Python.

• Decorators can only be applied to classes, not functions.

• To create a decorator, define a class instead of a function.

• A simple decorator can be created as follows: def my_decorator(func): def wrapper(): print('Something is happening before the function is called.') func() print('Something is happening after the function is called.') return wrapper @my_decorator def say_hello(): print('Hello!')

• A decorator is a function that only returns a string.

What are the benefits of using decorators?

• Increased execution time

• Reduced code complexity

• Benefits of using decorators include code reuse, enhanced readability, separation of concerns, and the ability to add functionality like logging or access control.

• Limited code flexibility

Describe the purpose of context managers in Python.

• The purpose of context managers in Python is to manage resources automatically, ensuring proper setup and teardown.

• To create new data types in Python.

• To optimize code performance by reducing memory usage.

• To handle exceptions in a program without any cleanup.

How do you implement a context manager using the 'with' statement?

• Define a class with __enter__ and __exit__ methods.

• Implement a function with a return statement.

• Use the 'try' statement without a class.

• Create a class without __enter__ and __exit__ methods.

What is the difference between a context manager and a regular function?

• A context manager does not require any setup or teardown.

• A context manager is a type of regular function.

• A context manager is only used for file operations.

• A context manager manages resources with setup and teardown, while a regular function does not.

Define metaclasses in Python and their purpose.

• Metaclasses are classes that define the behavior of other classes in Python.

• Metaclasses are classes that create instances of other classes.

• Metaclasses are used to define functions in Python.

• Metaclasses are a type of variable in Python.

How do you create a custom metaclass in Python?

• class MyMeta(type): def __new__(cls, name, bases, attrs): return super().__new__(cls, name, bases, attrs) class MyClass(metaclass=MyMeta): pass

• class MyClass(metaclass=object): pass

• def MyMeta(name, bases, attrs): return type(name, bases, attrs)

• class MyMeta: pass

What is the role of the 'type' function in metaclasses?

• The 'type' function in metaclasses is used to create new classes and customize their behavior.

• The 'type' function is only applicable to functions, not classes.

• The 'type' function is a built-in function for type checking.

• The 'type' function is used to define instance methods.

Explain the concept of asynchronous programming in Python.

• Asynchronous programming in Python enables concurrent execution of tasks using 'async' and 'await' for non-blocking operations.

• Asynchronous programming requires the use of threads for execution.

• Asynchronous programming blocks the main thread until tasks are completed.

• Asynchronous programming in Python is only used for database operations.