Python Code Completion Exercises

ExercisesCore

Complete the Python Objects, Values, Types, and Identity Code

Practice reasoning about identity, mutation, equality, and hashability with small Python programs.

~10 min read Start exercise

ExercisesBeginner

Complete the Python None code

Practice returning None, checking for None, and distinguishing None from other false values.

~6 min read Start exercise

ExercisesBeginner

Complete the Python Numbers code

Practice constructing complex numbers, reading their components, combining them with arithmetic, and promoting a real value to complex.

~8 min read Start exercise

ExercisesBeginner

Complete the Python range code

Practice constructing ascending and descending ranges, testing membership, and slicing range sequences.

~6 min read Start exercise

ExercisesBeginner

Complete the Python zip code

Practice pairing iterables, enforcing equal lengths, combining several inputs, and unzipping paired data.

~6 min read Start exercise

ExercisesBeginner

Complete the Python Iterable Unpacking code

Practice exact unpacking, starred targets, nested targets, and value swapping.

~6 min read Start exercise

ExercisesBeginner

Complete the Python map and filter code

Practice transforming, selecting, combining iterables, and composing map with filter.

~6 min read Start exercise

ExercisesBeginner

Complete the Python sorting code

Practice sorting iterables, using key functions, ordering multiple fields, and choosing list.sort().

~6 min read Start exercise

ExercisesBeginner

Complete the Python aggregation code

Practice all(), any(), min(), max(), and sum().

~6 min read Start exercise

ExercisesBeginner

Complete the Python numeric built-ins code

Practice abs(), divmod(), and pow().

~6 min read Start exercise

ExercisesIntermediate

Complete the Python recursion code

Practice base cases, recursive steps, and recursive traversal.

~7 min read Start exercise

ExercisesIntermediate

Complete the Python formatting code

Practice format specifications for width, alignment, numeric precision, and dynamic formatting.

~6 min read Start exercise

ExercisesIntermediate

Complete the Python coroutine code

Practice defining coroutine functions, awaiting other coroutines, and running an async entry point.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python asynchronous iteration code

Practice implementing and consuming asynchronous iterators with async for, aiter(), and anext().

~8 min read Start exercise

ExercisesIntermediate

Complete the Python asynchronous generator code

Practice defining asynchronous generators, preserving state across yields, stopping early, and using aclose() or contextlib.aclosing() for deterministic cleanup.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python asynchronous context managers code

Practice implementing __aenter__() and __aexit__(), handling asynchronous cleanup and exception behavior, and using async with.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python enumerations code

Practice defining enum members, looking up a value, iterating over members, and rejecting accidental aliases.

~7 min read Start exercise

ExercisesIntermediate

Complete the Python object-copying code

Practice making shallow copies, deep copies, preserving recursive structures, and replacing selected record fields.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python deque code

Practice adding and removing items at either end, bounded history, and rotation.

~8 min read Start exercise

ExercisesBeginner

Complete the Python modules and imports code

Practice importing modules, selecting names, using aliases, and protecting top-level program code.

~7 min read Start exercise

ExercisesBeginner

Complete the Python tuples and sets code

Practice tuple construction and unpacking, set creation and operations, and immutable set values.

~7 min read Start exercise

ExercisesAdvanced

Complete Python custom subscription, Sequence, Mapping, and Set code

Practice subscription, assignment, deletion, reverse iteration, and implementing the collections.abc Sequence, Mapping, and Set contracts.

~12 min read Start exercise

ExercisesIntermediate

Complete the argparse code

Practice typed arguments, option defaults, boolean flags, and subcommands.

~9 min read Start exercise

ExercisesIntermediate

Complete the asynchronous unittest code

Practise coroutine test methods, awaited exception checks, async cleanup, and await-specific mock assertions.

~10 min read Start exercise

ExercisesIntermediate

Complete the collections.Counter code

Practice counting iterable items, adding counts, preserving subtracted counts, and intersecting multisets.

~9 min read Start exercise

ExercisesIntermediate

Complete the collections.defaultdict code

Practice grouping values, collecting unique labels, reading without insertion, and creating independent per-key records.

~8 min read Start exercise

ExercisesIntermediate

Complete the command-line stream and exit-status code

Practise accessing argument tokens, routing diagnostics, reading standard input, and propagating a command exit status.

~10 min read Start exercise

ExercisesIntermediate

Complete the dates and times code

Practice date arithmetic, ISO parsing, aware UTC values, and named timezone conversion.

~8 min read Start exercise

ExercisesIntermediate

Complete the doctest code

Practise writing stable docstring examples, documenting exceptions, distinguishing returned and printed output, and testing examples in text files.

~12 min read Start exercise

ExercisesIntermediate

Complete the environment configuration code

Practise optional lookups, required settings, numeric validation, and explicit Boolean parsing.

~10 min read Start exercise

ExercisesIntermediate

Complete the ExitStack code

Practise entering dynamic synchronous and asynchronous resources, registering cleanup callbacks, handling partial acquisition, and transferring cleanup ownership.

~10 min read Start exercise

ExercisesIntermediate

Complete the filecmp comparison code

Practise byte-accurate comparison, cmpfiles classification, dircmp results, and cache refresh.

~12 min read Start exercise

ExercisesIntermediate

Complete the filesystem metadata code

Practise querying stat results, interpreting mode bits, inspecting links, and handling expected filesystem errors.

~12 min read Start exercise

ExercisesIntermediate

Complete the function-caching code

Practice caching deterministic results, limiting stored entries, clearing stale data, and inspecting cache hits.

~8 min read Start exercise

ExercisesIntermediate

Complete the glob and fnmatch code

Practise rooted pathname matching, lazy recursive search, explicit case-sensitive matching, and literal pattern escaping.

~12 min read Start exercise

ExercisesIntermediate

Complete the itertools code

Practice flattening, limiting, batching, grouping consecutive records, and building combinations with itertools.

~11 min read Start exercise

ExercisesIntermediate

Complete the os.scandir() code

Practise scanning directories, filtering DirEntry objects, handling cached status data, and closing iterators safely.

~12 min read Start exercise

ExercisesIntermediate

Complete the partial-function and method code

Practice pre-filling callable arguments and defining methods with functools.partialmethod while preserving instance binding.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python __init_subclass__ Code

Practice configuring, validating, and registering subclasses with __init_subclass__.

~8 min read Start exercise

ExercisesAdvanced

Complete the Python new and Object Creation Code

Practice the creation order, subclass-aware __new__(), immutable-value construction, and the boundary where __init__ is skipped.

~8 min read Start exercise

ExercisesAdvanced

Complete the Python slots Code

Practice declaring slots, restricting attributes, allowing a dictionary explicitly, and using slots across inheritance.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python annotations code

Practice annotated assignment syntax and the compatibility behavior of explicitly stringized annotations.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python argument unpacking code

Practice unpacking iterables and mappings into function calls with * and **.

~9 min read Start exercise

ExercisesIntermediate

Complete the Python assert statements code

Practice writing assertions, attaching diagnostic messages, and choosing explicit exceptions when a check must always run.

~8 min read Start exercise

ExercisesCore

Complete the Python Assignment Expressions Code

Practice using := to capture values in conditions, loops, and expressions while keeping ordinary assignment separate.

~10 min read Start exercise

ExercisesCore

Complete the Python Augmented Assignment Code

Practice updating names, mutable objects, attributes, and indexed values with augmented assignment.

~10 min read Start exercise

ExercisesIntermediate

Complete the Python bisect code

Practise finding left and right insertion points, inserting while preserving order, and maintaining a list of records by key.

~8 min read Start exercise

ExercisesBeginner

Complete the Python Boolean operators code

Practice using short-circuit and/or expressions to select values, guard access, and avoid unnecessary calls.

~8 min read Start exercise

ExercisesCore

Complete the Python Bytes and Bytearray Code

Practice constructing bytes, decoding binary data, mutating bytearray, and reading hexadecimal byte values.

~10 min read Start exercise

ExercisesAdvanced

Complete the Python Callable Object Code

Practice making instances callable with __call__ and using callable-object behavior.

~9 min read Start exercise

Exercises

Complete the Python Class and Static Methods Code

Practice creating class methods, static methods, and subclass-aware class methods.

~8 min read Start exercise

ExercisesAdvanced

Complete the Python Class Subscription Code

Practice implementing __class_getitem__ for class subscription and generic-style parameterization.

~9 min read Start exercise

ExercisesBeginner

Complete the Python classes and objects code

Practice defining a class, initializing instance state, adding methods, and extending a base class.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python comprehensions code

Practice writing list, set, and dictionary comprehensions and using filters.

~8 min read Start exercise

ExercisesBeginner

Complete the Python conditional expressions code

Practice choosing values with conditional expressions, composing them with larger expressions, and recognizing when the syntax should stay simple.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python context managers code

Practice with statements, implementing context-manager protocols, cleanup, narrow exception suppression, borrowing caller-owned resources with nullcontext(), and closing legacy resources.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python CSV code

Practice reading and writing CSV rows and using dictionary-based CSV access.

~8 min read Start exercise

ExercisesAdvanced

Complete the Python Custom Attribute Access Code

Practice customizing attribute reads, fallback lookup, assignment, and deletion safely.

~9 min read Start exercise

ExercisesAdvanced

Complete the Python Custom isinstance() and issubclass() Code

Practice implementing metaclass hooks that customize isinstance() and issubclass().

~10 min read Start exercise

ExercisesIntermediate

Complete the Python Dataclasses Code

Practice generated class methods, per-instance mutable defaults, post-initialization, and frozen data records.

~9 min read Start exercise

ExercisesIntermediate

Complete the Python decorators code

Practice applying function and class decorators, forwarding wrapper calls, preserving function metadata, configuring factories, and composing decorators.

~10 min read Start exercise

ExercisesIntermediate

Complete the Python del statements code

Practice deleting name bindings, list targets, slices, and attributes with Python's del statement.

~8 min read Start exercise

ExercisesAdvanced

Complete the Python Descriptor Code

Practice implementing __get__, __set_name__, __set__, and __delete__ in reusable descriptors.

~9 min read Start exercise

ExercisesAdvanced

Complete the Python Exception Groups and except* code

Practice creating exception groups and handling their matching subgroups with except*.

~7 min read Start exercise

ExercisesBeginner

Complete the Python exceptions and error handling code

Practice handling specific exceptions, using else and finally, and deliberately raising an exception.

~7 min read Start exercise

ExercisesIntermediate

Complete the Python file I/O code

Practice opening, reading, writing, appending, and selecting text or binary file modes.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python function parameters code

Practice positional-only, keyword-only, *args, and **kwargs parameters.

~8 min read Start exercise

ExercisesAdvanced

Complete the Python generator control code

Practice sending values into a paused generator, handling an injected exception, propagating one, and closing a generator with cleanup.

~10 min read Start exercise

ExercisesIntermediate

Complete the Python generator expressions code

Practice writing generator expressions and choosing them for lazy iteration.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python generators code

Practice writing generator functions, using yield, and creating generator expressions.

~8 min read Start exercise

ExercisesAdvanced

Complete the Python generic type parameters code

Practice generic functions, classes, type aliases, and multiple type parameters.

~9 min read Start exercise

ExercisesIntermediate

Complete the Python heapq code

Practice building a heap, adding priorities, removing the smallest item, and using a sequence tie-breaker.

~9 min read Start exercise

ExercisesIntermediate

Complete the Python iterators code

Practice creating and advancing iterators, implementing the iterator protocol, and stopping a callable iterator with a sentinel.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python JSON code

Practice serializing Python data, reading JSON text, and working with JSON files.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python lambda expressions code

Practice writing concise lambda expressions for direct calls, sorting, closures, and predicates.

~8 min read Start exercise

ExercisesIntermediate

Complete the Python logging code

Practice recording events with correct levels, deferred message arguments, exception tracebacks, and formatter configuration.

~9 min read Start exercise

ExercisesAdvanced

Complete the Python Metaclasses and Class Creation Code

Practice dynamic class creation, metaclass delegation, class-namespace validation, and namespace preparation.

~9 min read Start exercise

ExercisesAdvanced

Complete the Python Module Attribute Access Code

Practice defining module fallback values, raising AttributeError, exposing dynamic names through dir(), and caching a lazily resolved value.

~9 min read Start exercise

ExercisesIntermediate

Complete the Python Multiple Inheritance and MRO Code

Practice multiple base classes, inspect the MRO, and build a cooperative super() chain.

~9 min read Start exercise

ExercisesIntermediate

Complete the Python operator precedence code

Practice grouping expressions explicitly, applying operator precedence, and reasoning about evaluation order.

~9 min read Start exercise

ExercisesBeginner

Complete the Python packages and imports code

Practice creating package imports, accessing submodules, and using a relative import inside a package.

~7 min read Start exercise

ExercisesIntermediate

Complete the Python paths and pathlib code

Practice composing, searching, comparing, normalizing, expanding, splitting, and converting filesystem paths with pathlib and selected os.path functions, including drive/root/tail decomposition, path identity, environment-variable expansion, and str/bytes interoperability.

~18 min read Start exercise

ExercisesIntermediate