Advanced Python & Libraries - MCQ Practice Test

Question 1

Which of the following statements about the Python Global Interpreter Lock (GIL) is TRUE as of early 2026 for CPython?

The GIL allows multiple CPU-bound Python threads to execute simultaneously on multi-core processors. The GIL is primarily released during I/O operations, making threading efficient for I/O-bound tasks. The GIL is a mechanism present in all Python implementations (e.g., Jython, IronPython, PyPy). asyncio programs bypass the GIL, enabling true parallel execution of CPU-bound coroutines.

Question 2

You are working with a large Pandas DataFrame. Which operation is generally the most performant way to apply a custom function to a column?

df['Value'].apply(my_func) Using a Python for loop to iterate through df['Value'] and apply my_func Vectorizing my_func using NumPy operations or a library like numba df['Value'].map(my_func)

Question 3

In Python's asyncio framework, what is the primary purpose of the await keyword?

To immediately execute a synchronous function in a separate thread To pause the execution of the current coroutine and yield control to the event loop, allowing other tasks to run To force the execution of a CPU-bound task in parallel To define a new asynchronous function

Question 4

To enforce that an API endpoint can only be accessed by authenticated users with an 'admin' role, which pattern would you most likely employ?

Aspect-Oriented Programming (AOP) with method interception Custom Decorators or Middleware Using Python's logging module to check user roles Storing role information directly in the HTTP request body

Question 5

What will be the output when accessing a non-existent key in a defaultdict(list)?

KeyError: 'D' [] None 0

Question 6

You want users to register custom functions at specific points in your application's lifecycle. Which pattern is best suited?

Inheritance with Abstract Base Classes Dependency Injection with explicit factory functions Decorators or a Plugin System Using exec() and eval() for runtime code execution

Question 7

Which of the following is a key characteristic of a Python data descriptor?

It only defines the __get__ method It takes precedence over an instance's __dict__ when resolving an attribute lookup It is typically stored in the instance's __dict__ It cannot be used with the property built-in function

Question 8

Which library provides the most optimized way to calculate the dot product of two large 1D arrays?

Python's built-in math module The collections module The NumPy library Python's standard list operations with a generator comprehension

Question 9

In a FastAPI application, what is the primary purpose of defining path parameters (e.g., @app.get('/items/{item_id}'))?

To specify optional query parameters that can be passed in the URL To define the type of HTTP request method (GET, POST, PUT, DELETE) To extract variable segments from the URL path as arguments to the path operation function To validate the entire request body against a Pydantic model

Question 10

Which module from Python's standard library is best suited for executing external commands and interacting with their input/output streams securely?

os.system() subprocess shutil pathlib