PCPP2 Practice Test 14 — 15 Questions

Question 1

You are managing subprocesses using subprocess.Popen. Which attribute of the Popen object should you check to verify the exit code after the process terminates?

Accepted Answer

returncode. The returncode attribute is populated after the process finishes or wait() is called.

Answer

code

Answer

status

Answer

poll()

Answer

exit_code

Question 2

Which TWO of the following are valid ways to synchronize threads?

Accepted Answer

threading.Semaphore. Locks and Semaphores are fundamental threading synchronization primitives.

Answer

threading.ProcessPool

Answer

threading.Queue

Answer

threading.Process

Question 3

Which THREE of the following represent ways to synchronize access to shared data in a multi-threaded application?

Accepted Answer

threading.Lock. Locks, Semaphores, and Events are core tools for controlling access and state between threads.

Answer

threading.System

Answer

threading.Process

Question 4

When implementing the Bridge pattern, what is the primary structural requirement to effectively decouple an abstraction from its implementation?

Accepted Answer

The abstraction must contain an instance of the implementation interface. The abstraction must contain a reference (bridge) to an object of an implementor interface, allowing the implementation to vary independently.

Answer

The implementation must use a Singleton to manage its state

Answer

Both the abstraction and the implementation must inherit from the same class

Answer

The implementation must be a subclass of the abstraction

Question 5

When using socket.setsockopt(), which option is required to immediately reuse a port that is currently in a TIME_WAIT state after a server restart?

Accepted Answer

socket.SO_REUSEADDR. SO_REUSEADDR allows a socket to bind to an address/port that is currently in the TIME_WAIT state.

Answer

socket.TCP_NODELAY

Answer

socket.SO_LINGER

Answer

socket.SO_KEEPALIVE

Question 6

Which TWO of the following are differences between TCP and UDP?

Accepted Answer

TCP has higher overhead than UDP.. TCP is reliable and connection-oriented, whereas UDP is connectionless and unreliable.

Answer

UDP is connection-oriented.

Answer

UDP is always faster than TCP in every network condition.

Answer

TCP supports multicasting natively.

Question 7

You are using Pool.apply_async(). How do you retrieve the result of the function call?

Accepted Answer

Call the get() method on the returned object.. The apply_async method returns an AsyncResult object, and you must call the get() method on it.

Answer

Wait for the function to return.

Answer

Use the join() method on the pool.

Answer

Pass a callback function.

Answer

Check the pool's result list.

Question 8

You are utilizing the Mediator pattern to reduce coupling between components. Which of the following describes the role of the Mediator?

Accepted Answer

It acts as a central hub that coordinates interactions between components. The Mediator centralizes communication between components, so they don't need to refer to each other directly.

Answer

It allows components to communicate directly with each other

Answer

It enforces that components are implemented as Singletons

Answer

It is responsible for data storage for all components

Question 9

Which TWO of the following are structural patterns?

Accepted Answer

Facade. Adapter and Facade are classic structural patterns.

Answer

Command

Answer

Observer

Answer

Builder

Question 10

Which 'unittest' assertion is best suited to verify that two floating-point numbers are equal within a certain tolerance?

Accepted Answer

assertAlmostEqual. assertAlmostEqual is specifically designed to handle floating-point precision issues by comparing values within a specified delta.

Answer

assertGreater

Answer

assertEqual

Answer

assertSequenceEqual

Question 11

Which of the following is the correct way to close a socket object in Python?

Accepted Answer

socket.close(). The close() method should be called on the socket object to release the underlying file descriptor.

Answer

socket.destroy()

Answer

socket.shutdown()

Answer

del socket

Question 12

Which THREE of the following are true regarding the use of the socket module in Python?

Accepted Answer

Sockets are identified by file descriptors in the OS.. Sockets are file descriptors, they can be set to non-blocking mode, and they must be closed to avoid resource leaks.

Answer

The send() method is guaranteed to send the entire buffer requested.

Answer

Closing a socket does not terminate the underlying file descriptor.

Question 13

Which TWO of the following are valid ways to implement the Proxy pattern in Python?

Accepted Answer

Inheriting from the target class and overriding its methods. Proxy can be implemented using class-based wrapping or by overriding magic methods like __getattr__.

Answer

Using the 'import' hook in the sys module

Answer

Using a decorator to modify the class structure

Answer

Changing the global variable scope

Question 14

Which TWO of the following are valid ways to pass data into a pytest test function?

Accepted Answer

Using function arguments that match fixture names. Fixtures and parametrization are the standard ways to inject data into pytest functions.

Answer

Defining global variables in the same file

Answer

Accessing the 'sys.argv' list

Answer

Using the 'unittest.TestCase' setup method

Question 15

Which method should a developer use to retrieve the IP address and port of the remote peer connected to a TCP socket?

Accepted Answer

socket.getpeername(). getpeername() returns the address of the remote endpoint connected to the socket.

Answer

socket.recvfrom()

Answer

socket.getsockname()

Answer

socket.getfqdn()