Challenge Library
Coding Challenges
5,893 curated questions across every arena — browse by topic, then jump into a live 3-minute battle to put them to the test.
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520 challenges matching your filters
Clear topic filter- Multiple ChoiceIntermediate
pytest Parametrize (MCQ)
pythonintermediate - Multiple ChoiceBeginner
unittest Module
pythonbeginner - Multiple ChoiceIntermediate
mock.patch
pythonintermediate - Multiple ChoiceIntermediate
MagicMock
pythonintermediate - Multiple ChoiceBeginner
assert Methods
pythonbeginner - Multiple ChoiceIntermediate
pdb Debugger
pythonintermediate - Multiple ChoiceIntermediate
doctest Module
pythonintermediate - Multiple ChoiceIntermediate
cProfile Module
pythonintermediate - Multiple ChoiceIntermediate
coverage.py
pythonintermediate - Multiple ChoiceIntermediate
pytest.raises
pythonintermediate - Multiple ChoiceIntermediate
Mock Return Value
pythonintermediate - Multiple ChoiceBeginner
Test Discovery
pythonbeginner - Multiple ChoiceBeginner
Test Coverage Report
pythonbeginner - Code AnalysisIntermediate
pytest parametrize (Analysis)
pythonintermediate - Code AnalysisBeginner
mock return_value
pythonbeginner - Code AnalysisBeginner
assertEqual output
pythonbeginner - Code AnalysisIntermediate
assertRaises context
pythonintermediate - Code AnalysisIntermediate
patch decorator
pythonintermediate - Code AnalysisIntermediate
doctest example
pythonintermediate - Code AnalysisIntermediate
MagicMock attributes
pythonintermediate - Code AnalysisHard
Class Variable Shadow
code-analysisPythonlanguage - Code AnalysisHard
Decorator Order
code-analysisPythonlanguage - Code AnalysisBeginner
Dict Merge 3.9+
code-analysisPythonlanguage - Code AnalysisBeginner
F-string Format Spec
code-analysisPythonlanguage - Code AnalysisIntermediate
Generator Exhaustion
code-analysisPythonlanguage - Code AnalysisHard
is vs == (int cache)
code-analysisPythonlanguage - Code AnalysisIntermediate
Lambda Late Binding
code-analysisPythonlanguage - Code AnalysisIntermediate
List Comp Scope
code-analysisPythonlanguage - Code AnalysisHard
Multiple Inheritance MRO
code-analysisPythonlanguage - Code AnalysisHard
Mutable Default Arg
code-analysisPythonlanguage - Code AnalysisIntermediate
nonlocal Keyword
code-analysisPythonlanguage - Code AnalysisBeginner
Reversed String
code-analysisPythonlanguage - Code AnalysisBeginner
Set Comprehension
code-analysisPythonlanguage - Code AnalysisBeginner
Star Unpacking
code-analysisPythonlanguage - Code AnalysisHard
String Interning
code-analysisPythonlanguage - Code AnalysisBeginner
Truthiness Edge Cases
code-analysisPythonlanguage - Code AnalysisIntermediate
Try Else Finally Order
code-analysisPythonlanguage - Code AnalysisIntermediate
Tuple Mutable Item
code-analysisPythonlanguage - Code AnalysisHard
Walrus in Comprehension
code-analysisPythonlanguage - Code AnalysisBeginner
Unequal Zip
code-analysisPythonlanguage - Multiple ChoiceBeginner
[Python] *args Variable argument handling
qapythonpythonqa - Multiple ChoiceBeginner
[Python] **kwargs Variable argument handling
qapythonpythonqa - Multiple ChoiceBeginner
[Python] Unpack to call Variable argument handling
qapythonpythonqa - Multiple ChoiceBeginner
[Python] Unpack list Variable argument handling
qapythonpythonqa - Multiple ChoiceBeginner
[Python] Order Variable argument handling
qapythonpythonqa - Multiple ChoiceHard
[Python] Event loop Single-thread cooperative multitasking
qapythonpythonqa - Multiple ChoiceHard
[Python] gather Single-thread cooperative multitasking
qapythonpythonqa - Multiple ChoiceHard
[Python] create_task Single-thread cooperative multitasking
qapythonpythonqa - Multiple ChoiceHard
[Python] Semaphore Single-thread cooperative multitasking
qapythonpythonqa - Multiple ChoiceHard
[Python] TaskGroup Single-thread cooperative multitasking
qapythonpythonqa - Multiple ChoiceIntermediate
[Python] File open with statement for setup/teardown
qapythonpythonqa - Multiple ChoiceIntermediate
[Python] Custom with statement for setup/teardown
qapythonpythonqa - Multiple ChoiceIntermediate
[Python] @contextmanager with statement for setup/teardown
qapythonpythonqa - Multiple ChoiceIntermediate
[Python] Multiple with statement for setup/teardown
qapythonpythonqa - Multiple ChoiceIntermediate
[Python] ExitStack with statement for setup/teardown
qapythonpythonqa - Multiple ChoiceBeginner
[Python] @dataclass Auto __init__, __repr__, __eq__
qapythonpythonqa - Multiple ChoiceBeginner
[Python] field() Auto __init__, __repr__, __eq__
qapythonpythonqa - Multiple ChoiceBeginner
[Python] frozen Auto __init__, __repr__, __eq__
qapythonpythonqa - Multiple ChoiceBeginner
[Python] __post_init__ Auto __init__, __repr__, __eq__
qapythonpythonqa - Multiple ChoiceBeginner
[Python] Order Auto __init__, __repr__, __eq__
qapythonpythonqa
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