O","domainSlug":"exceptions-file-io"},{"id":"062eafd7-62f1-4666-8a38-0ee6a343c2e8","slug":"refer-to-the-exhibit-what-is-the-output-note-actual-mro-teiqj","questionText":"Refer to the exhibit. What is the output? (Note: actual MRO may vary; choose the one that matches Python 3 C3 linearization.)","explanation":"Python 3 uses C3 linearization to compute the Method Resolution Order (MRO). For class D inheriting from B and C, which both inherit from A, the MRO is D, B, C, A, object. This satisfies the monotonicity and local precedence order: B comes before C (as per D's bases), and A is last among the user-defined classes, with object always appended.","domainId":"436b3e49-1903-487c-b11e-2a225d35661a","difficulty":"hard","questionType":"multiple_choice","pbqConfig":null,"exhibitText":"class A:\n def method(self):\n return \"A\"\n\nclass B(A):\n def method(self):\n return \"B\"\n\nclass C(A):\n def method(self):\n return \"C\"\n\nclass D(B, C):\n pass\n\nprint(D.__mro__)","options":[{"id":"a11e3c09-f80b-4f2f-a4ce-83c97e99bae0","label":null,"text":"(, , , )","isCorrect":false},{"id":"bb69da03-4684-48ab-97e7-863a68fb29e8","label":null,"text":"(, , , , )","isCorrect":true},{"id":"571f18e3-9172-46fb-a363-1569a362e1b3","label":null,"text":"(, , , , )","isCorrect":false},{"id":"34f37ec3-5d77-477a-b8d3-1dc9cf6e345c","label":null,"text":"(, , , , )","isCorrect":false}],"domainName":"Object-Oriented Programming","domainSlug":"oop"},{"id":"fbb7d474-280d-45c4-8905-95bef0dfb75a","slug":"a-programmer-writes-a-function-that-expects-a-string-and-ret-drvdp","questionText":"A programmer writes a function that expects a string and returns it reversed. Which code snippet correctly reverses the string 'stressed' to 'desserts'?","explanation":"Both option B and option D correctly reverse the string 'stressed' to 'desserts'. Option B uses slice notation `[::-1]`, which creates a reversed copy of the string by stepping from end to start with a step of -1. This is the most direct and idiomatic way to reverse a string in Python. Option D uses `''.join(reversed(s))`: `reversed(s)` returns an iterator that yields characters in reverse order, and `join()` concatenates them into a new string. This is also a valid and correct approach. Option A is incorrect because strings do not have a `reversed()` method; `reversed()` is a built-in function. Option C is incorrect because `.reverse()` is a list method, not a string method, and strings are immutable.","domainId":"622afe46-2129-4c9a-9177-6d05e399a4ac","difficulty":"easy","questionType":"multiple_choice","pbqConfig":null,"exhibitText":null,"options":[{"id":"649f1ee3-5a23-4944-9a08-ce3681850f7f","label":null,"text":"result = s.reversed()","isCorrect":false},{"id":"df6f8d1b-bd93-4131-bd3c-74ee62745697","label":null,"text":"result = s[::-1]","isCorrect":true},{"id":"727213ca-a46b-4945-a65c-1dfdd71a343a","label":null,"text":"s.reverse()","isCorrect":false},{"id":"3532a057-8853-4af3-bbc0-a346459e20bf","label":null,"text":"result = ''.join(reversed(s))","isCorrect":true}],"domainName":"Strings","domainSlug":"strings"},{"id":"c0013774-eb28-4dd9-90c2-4cc5f99d3e21","slug":"you-are-a-python-developer-working-on-a-project-with-the-fol-pmrpp","questionText":"You are a Python developer working on a project with the following structure:\n\nmyapp/\n __init__.py\n main.py\n modules/\n __init__.py\n utils.py\n helpers.py\n\nThe file main.py contains:\n\nfrom modules import utils\nfrom modules import helpers\n\nutils.some_function()\nhelpers.another_function()\n\nWhen you run main.py, you get an ImportError: No module named 'modules'. However, the modules directory exists and both __init__.py files are