tions":[{"id":"723b3f11-4a19-4a90-a6b9-4028ef9cd6e1","label":null,"text":"if statements are harder to read and maintain.","isCorrect":false},{"id":"7773d216-feb8-46f0-aa57-b0a4c9c7e06d","label":null,"text":"try-except can catch multiple exception types more cleanly.","isCorrect":false},{"id":"db7d11c9-c59b-42f4-8ab7-68e32776fa25","label":null,"text":"try-except blocks have no performance cost at all.","isCorrect":false},{"id":"44e888b6-5233-4282-816d-e8963cbc1d16","label":null,"text":"LBYL leads to race conditions in concurrent code because the file's state can change between the check and the use.","isCorrect":true}],"domainName":"Exceptions and File I/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":"16fc41c6-e74b-4f61-b703-7f6d92cd8d01","slug":"match-each-python-data-structure-to-its-mutability-78sll","questionText":"Match each Python data structure to its mutability.","explanation":"In Python, list, dict, and set are mutable data structures, meaning their contents can be modified. Tuple, string, and frozenset are immutable; their contents cannot be changed after creation. Common confusions include thinking tuples are mutable (they are not) or that frozensets are mutable (they are not).","domainId":"2b014ac6-8f8c-483a-a46c-692349fd825f","difficulty":"medium","questionType":"matching","pbqConfig":null,"exhibitText":null,"options":[{"id":"61ae1569-9ded-424c-9bea-2d0e678683aa","label":null,"text":"list: Mutable","isCorrect":true},{"id":"96162c7d-486d-4570-8dae-add463493ecf","label":null,"text":"tuple: Mutable","isCorrect":false},{"id":"33051583-268a-48a8-960c-2495730beb9f","label":null,"text":"dict: Mutable","isCorrect":true},{"id":"e78d774f-1aa9-44f5-b6f2-19976f2fe361","label":null,"text":"set: Immutable","isCorrect":false},{"id":"9040e18d-02af-460b-8852-e9c37fe1f218","label":null,"text":"string: Immutable","isCorrect":true},{"id":"6302bde0-5653-4ffb-8315-3d7c5999b536","label":null,"text":"frozenset: Mutable","isCorrect":false}],"domainName":"Exceptions and File I/O","domainSlug":"exceptions-file-io","matchingPairs":[{"id":"27c3fc6d-47c9-4bf4-99dc-f345dae1a707","leftItem":"list","rightItem":"Mutable","displayOrder":0},{"id":"b58ec2a2-6709-4a4e-91a3-eb6e38b64bde","leftItem":"tuple","rightItem":"Immutable","displayOrder":1},{"id":"88d4aabb-935c-4ef1-87df-c7