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add Sum up lists-of-lists of numbers

comprehensionslooping

Circle Class representing a Circle, with auto-updating attributes

classespropertiesmath

count_words Count occurrences of each word in a string

regular expressionsdictionariesloopingfunction

tail Return last N items in a given iterable

iteration toollistloopingfunctionslicing

parse_ranges Parse comma-delimited numeric ranges

regular expressionscomprehensionsgeneratorstext processingmaking iterators

dollars Script to display a number as US currency

command line interfaces

to_percent Convert a ratio to a percentage

last_n_elements Get the last N items in a list

listconditionalsfunctionslicing

zero Command-line program that prints eighty 0's

loopingargument parsingcommand line interfaces

swap_ends Swap first and last items in a list

split_in_half Split a list into two halves

listfunctionslicing

combine_lists Combine two lists into one

listloopingfunction

head Get the first N items from any iterable

iteration toolcomprehensionslistgeneratorsmaking iteratorsloopingfunction

characters Get a list of lowercased characters from a string

listsortingfunction

line_numbers Program to print lines from a file with their line numbers

loopingcommand line interfacesfunction

reverse_words Reverse words in the given string

listfunctionslicing

flip_dict Flip keys and values in a dictionary.

dictionarieslooping

Point Class representing a 3-dimensional point

classesdataclassesgeneratorsdunder methodsmaking iterators

has_duplicates Determine whether a list has duplicate items

listloopingslicing

jot Script for quickly jotting down ideas for later

command line interfacesfile navigation

len_or_none Return return the length or None (if no length)

exception handlingfunction

is_anagram Determine whether the given words are anagrams

dictionariestext processingunicodefunction

total_air_travel Add up all air travel expenses in a CSV file

csvfile processingargument parsingcommand line interfaces

lucas Generate numbers from the Lucas sequence in your terminal

text processingcommand line interfaces

transpose Transpose a given list-of-lists

comprehensionslistloopingfunction

fix_csv.py Convert pipe-delimited files to comma-delimited files

csvlistfile processingargument parsingcommand line interfaces

matrix_from_string Turn a string into a list-of-lists of numbers

comprehensionsmathlistloopingfunction

rotate_list Rotate item from one end of a list to the other

listconditionals

dict_from_tuple Turn list-of-tuples into a multi-valued dictionary

dictionariesloopingfunction

NextDate Find date of the next given weekday

classesdataclasses

roll Simulate dice rolls.

mathargument parsingcommand line interfaces

fix_newlines Enforce final newlines and normalize file line endings

text processingloopingfile processingcommand line interfacesconditionals

meetup_date Find N-th occurrence of a specific weekday in the month

comprehensionsfunction

is_perfect_square Determine whether a number is a perfect square

sort_dict Sort a dictionary by its keys

dictionariessortinglooping

call_later Create a function to call another function at a later time

rock paper scissors Implement the game rock-paper-scissors

dictionariesargument parsingcommand line interfacesconditionals

input_number Prompt a user to enter a number

exception handling

ProxyDict Immutable dictionary-like wrapper around a dictionary

classesmaking iterators

to_jsonl Convert a JSON array file to a JSONL file

file processingcommand line interfaces

uniques_only Get unique items from an iterable while maintaining item order

iteration toollistgeneratorsmaking iteratorsloopingfunctionslicing

print_call_time Decorator to the print time a function took to run

mask keys Mask sensitive dictionary keys

dictionariesrecursion

duplicates_only Refactor duplicate-checking function to improve performance

dictionariesefficiency

jsonify Decorator to JSON-encode a function's return value

deep_add Deeply sum numbers in an iterable-of-iterables

recursionlooping

strip_lines Get all lines from a file with newlines removed

iteration toolcomprehensionsgeneratorsmaking iteratorsloopingfile processingfunction

four Repeatedly count the letters within a number

mathtext processingloopingcommand line interfacesconditionals

float_range range-like utility for floating point numbers

classesiteration toolmathgeneratorsdunder methodsloopingefficiency

groot A decorator that always prints "Groot"

sum_timestamps Sum up a list of MM:SS timestamp strings

regular expressionscomprehensionsgenerators

get_shared_keys Find the common keys between two dictionaries

dictionariesfunction

csv_columns Turn CSV rows into a dictionary mapping headers to columns

dictionariescomprehensionslistloopingfile processing

first Get the first item from any iterable

BankAccount Class representing a bank account with read-only balance

classesproperties

only_once Decorator that only allows functions to be called once

paste_code A function to help paste code into the Python REPL

loopingexception handlingfunction

format_ranges Format list of numbers into groups of start-stop strings

comprehensionslistgeneratorstext processingsortinglooping

flatten_dict Flatten a dictionary-of-dictionaries

dictionariescomprehensionsrecursionlooping

sort Sort the lines in a file

text processingsortingfile processingcommand line interfaces

window Get each iterable item and the next N-1 items

iteration toolgeneratorsdunder methodsmaking iteratorslooping

Row Class that accepts any given keyword arguments

suppress Context manager that suppresses specific exceptions

classescontext managersdataclassesdecoratorsgeneratorsexception handling

is_iterator Determine whether an iterable is an iterator

chunked Break an iterable into N-length chunks

iteration toolcomprehensionsgeneratorsmaking iteratorsloopingslicing

EasyDict Dictionary-like class supporting both attribute and key lookups

interleave Interleave items from each of the given iterables

iteration toolcomprehensionslistgeneratorsmaking iteratorslooping

dramatic print Print text character-by-character

reformat_diary.py Program to reformat a diary file into multiple files

regular expressionscomprehensionsgeneratorstext processingcommand line interfacesfile navigation

PhoneNumber Class representing a US phone number

classesregular expressions

format_fixed_width Format rows into a string of fixed-width columns

comprehensionslistgeneratorstext processingternary operator

OrderedSet Set-like object that maintains insertion-order of items

classesgeneratorsdunder methodsmaking iteratorsefficiency

tags_equal Determine whether two HTML tags are equivalent

regular expressionscomprehensionstext processingternary operatorslicing

Month Class representing a month and year

classespropertiesdataclassesslotsdunder methodsefficiency

minmax Return both minimum and maximum values in an iterable

dataclassesloopingternary operator

count_calls Decorator that counts the calls to a function

classespropertiesdecorators

maybe An object that is randomly truthy or falsey

classesdunder methods

remove_empty Remove all empty directories recursively

command line interfaces

CyclicList List-like class that loops in a cyclic manner

classesiterable classgeneratorsmaking iterators

deep_flatten Flatten deeply nested iterable-of-iterables

iteration toolrecursiongeneratorsmaking iteratorslooping

print_call_info Create a decorator that prints function call info

all_same Determine whether all items in an iterable are the same

generatorsloopingfunction

MaxCounter A Counter that can identify all most common keys

Vector Class representing 3-dimensional vector

classesdataclassesslotsgeneratorsdunder methodsmaking iteratorsefficiency

pluck Tool to deeply query a dictionary of dictionaries

dictionariesrecursiontext processingexception handling

fixed2csv.py Convert fixed-width file to CSV file

csvcomprehensionslistgeneratorsloopingfile processingargument parsingcommand line interfacesslicing

float_range (part 2) range-like utility for floating point numbers

classesiterable classiteration toolmathdunder methodsloopingefficiencyslicing

window (part 2) Get each iterable item and the next N-1 items

iteration toolcomprehensionsgeneratorsmaking iteratorsloopingslicing

count_lines Calculate line count for all .py files in a directory

classesdataclassestext processingexception handlingfile navigation

alias A helper that (magically?) alias one attribute to another

classespropertiesdataclassesdescriptors

total_length Find the number of items in all given iterables

comprehensionsgeneratorslooping

PermaDict Dictionary-like objects which don't allow key updates

classesdunder methodsmaking iterators

sort_by_column.py Program to sort a CSV file by specific columns

csvcomprehensionssortingfile processingargument parsingexception handlingcommand line interfaces

FuzzyString String-like class supporting case-insensitive comparisons

classestext processingunicode

minmax (part 2) Getting minimum and maximum values from an iterable (again)

dataclassescomprehensionsloopingternary operatorexception handling

ReverseView A sequence-like class representing the reverse of a given sequence

classesmaking iterators

Count votes Program to count votes for numerical options

regular expressionsdictionariestext processingcommand line interfaces

Timer Context manager to time blocks of code

classescontext managersdecorators

my_builtins Re-implement some built-in functions to learn how they work

generatorsloopingternary operatorexception handling

loop_helper A utility to get helpful information while looping

comprehensionsgeneratorslooping

RandomLooper Loop over iterable items in a random order

classesiterable classcomprehensionslistgeneratorsdunder methods

divide Divide an iterable into N parts

iteration toolcomprehensionsgeneratorsmaking iteratorsslicing

Unpacker Class supporting tuple unpacking of all attributes

classesiterable classdictionariesdunder methods

grades Convert percentages to US-style grades and calculate GPAs

dictionariesmathternary operatorconditionalsfunction

SequenceZip A fancy version of zip just for sequences

classescomprehensionsgeneratorsdunder methods

ini2csv.py Program to convert INI file to a CSV file

regular expressionscsvtext processingfile processingargument parsingcommand line interfacesslicing

Comparator Object to facilitate "almost equal" numerical comparisons

classescontext managersmath

cd Context manager for temporarily changing directories

classescontext managersdataclasses

markdownify Convert basic HTML to basic markdown

regular expressionstext processing

running_mean Utility to calculate a running mean while looping

mathgeneratorsloopingfunction

FancyReader CSV reader that returns friendly objects for each row

classesiterable classdictionariescsvmaking iteratorsfile processing

condense_csv Condense CSV text, to use fewer rows and more columns

dictionariescsvcomprehensionstext processingfile processing

Grouper Dict-like class which groups things using a key function

classesdunder methods

int_to_roman Convert integers to Roman numerals and back

text processingexception handling

MutableString String-like object that is mutable

classescontext managersdunder methodstext processing

strict_zip Like zip, but raises an error for iterables of different lengths

iteration toolcomprehensionsgeneratorsmaking iteratorsexception handling

make_file Context manager to create a temporary file

classescontext managers

normalize_sentences Make sure sentences have two spaces between them

regular expressionstext processingloopingslicing

PiecewiseRange Lazy iterable representing the concatenation of many ranges

classescomprehensionsgeneratorsdunder methodsternary operator

natural_sort Sort strings case-insensitively and numerically

regular expressionscomprehensionstext processingsortingternary operator

MonthDelta MonthDelta class that works along with Month class

classesdataclassesdunder methods

Timer (redux) Reusable context manager to time code blocks, including splitting

classescontext managersdunder methodsconstructor

ages Utilities related to working with birthdates and ages

text processing

record_calls Decorator that records calls to a function

classesdataclassesdecorators

last_lines Get the lines in a file in reverse order

regular expressionslisttext processingmaking iteratorsfile processingbinary filesslicing

FancyReader (redux) A memory-efficient version of csv.DictReader

classespropertiesslotsefficiency

loop_tracker An iterator with extra bells and whistles

propertiesiteration toolmaking iteratorsexception handling

format_bytes Format numbers into human-readable byte sizes

regular expressionsmathtext processingloopingternary operatorslicing

nostar A module that disallows * imports

cached_property Like the property decorator but values are cached

classespropertiesdecoratorsdescriptors

fancy_input Like the built-in input function, but fancier

loopingcommand line interfaces

SliceView A "view" into a sequence, like a lazy slice

iterable classmathrecursiongeneratorsmaking iterators

update_reviews Update one CSV file based on another CSV file

csvcomprehensionsfile processingargument parsingcommand line interfaces

ChainSequence Class to link sequences together

min_n Get the smallest n items in an iterable

listsortingslicing

final_class Making classes which cannot be subclassed.

decoratorsmetaclassesconstructor

concat_check.py Find implicit string concatenation in Python files

regular expressionsfile processingbinary filescommand line interfaces

ProxyDict (redux) Immutable dictionary-like wrapper around a dictionary

classesmaking iterators

file_looper Utility to open many files one after the other

comprehensionsgeneratorsmaking iteratorsfile processing

grep A utility like the Linux/Unix grep command

regular expressionsmathtext processingloopingargument parsingcommand line interfaces

RomanNumeral Class representing a Roman numeral

classesdunder methods

coalesce "Coalesce" a NULL value to a specific default value

decoratorscomprehensionsternary operator

computed_property Cached decorator that recomputes on specific attribute changes

classespropertiesdecoratorscomprehensionsdescriptors

easyjson Convert a JSON string to a JavaScript-like object

classescomprehensionsrecursion

find_duplicates Identifies duplicate files

file processingbinary filesefficiency

Check-writing helper Program to help write the amount/date for a cheque

mathtext processingcommand line interfacesconditionals

MinHeap A heap data structure

classesslotsefficiency

pattern_rename.py Program to rename files from one naming scheme to a different naming scheme

regular expressionscommand line interfaces

validators A descriptor that can only be assigned positive numbers

classesdescriptorsdunder methodsconstructorweak references

smoosh Weirdly-named utilities to flatten iterable of iterables

regular expressionsrecursion

iconv.py Convert text from one character encoding to another

unicodefile processingbinary filesargument parsingcommand line interfaces

instance_tracker Class factory which allows classes to track instances of themselves

constructorweak references

bullet points Utilities for parsing nested bullet points

classesdataclassesregular expressionscomprehensionsdunder methodstext processing

phonetic.py Program to spell words using the NATO phonetic alphabet

dictionariestext processingunicodeargument parsingcommand line interfaces

moviestats Utilities for asking questions of a JSON-based data file

dictionariescomprehensionslistsortingefficiency

SSH log parser Functions to extract data from a compressed SSH log file

dataclassesregular expressions

random_rename Program to to randomize filenames for blinded reviews

csvfile processingargument parsingcommand line interfaces

partial Utility to partially evaluate functions

classesdecoratorscomprehensionsgenerators

Version tests Tests for a Version class which represents a program version

classesdunder methodsexception handlingcommand line interfaces

easyclass A handy custom extension of the dataclass decorator

classesdataclassesiterable classdecorators

dmath Command-line utility for doing date math

exception handlingcommand line interfaces

FieldTracker Class that tracks which attributes have changed

classesdictionariescomprehensions

debug_calls Decorator that prints debug information for the called function

decoratorsintrospection

passphrase Command-line program that randomly generates 4-word passphrases

argument parsingcommand line interfaces

QueryList List-like class with methods for quick queries

classesiterable class

annual_return Calculate financial return rate over many years

regular expressionstext processingcommand line interfaces

plan_meeting Command-line program to help plan international meetings

regular expressionsfile processingargument parsingcommand line interfaces

my_builtins (redux) Re-implement some built-in functions to learn how they work

classesgeneratorsloopingconstructorexception handling

page Command-line tool for paginating text files by their lines

file processingargument parsingcommand line interfaces

reprtools Utilities to help implement __repr__ methods

decoratorscomprehensionsintrospection

SequenceZip (part 2) Like zip-like utility that can be looped over multiple times

classesgeneratorsdunder methods

positional_only Decorator requiring all arguments be positional-only arguments

classespropertiesdecoratorsconstructor

Circle (redux) Class representing a Circle, with auto-updating attributes

classespropertiescomprehensionsmathefficiency

checksum Program to validate file checksums

file processingbinary filescommand line interfaces

iospy Utilities to merge file streams and spy on I/O

classescontext managersproperties

EasyDict (part 2) Dictionary-like class supporting both attribute and key lookups

countdown Command-line visual countdown timer

comprehensionscommand line interfaces

fancy_map Like the built-in map function but can be looped over many times

classesiteration tooldunder methodsmaking iterators

crossword helper Command line util to generate crossword matches based on pattern

regular expressionsargument parsingcommand line interfaces

Tree Tree-like data structure that automatically spawns new branches

classesdictionariesrecursiondunder methods

bind Like functools.partial, but with placeholder arguments

fixed2csv2.py Program to convert fixed-width files to CSV files

regular expressionscsvcomprehensionslistloopingfile processingcommand line interfacesslicing

easyjson (redux) Convert a JSON string to a JavaScript-like object

diff_cols Program to compare specific columns in CSV files

csvargument parsingcommand line interfaces

ratelimit Decorator to rate-limit calls to a function

classesdecorators

zipit A CLI for making ZIP files from Python programs

binary filescommand line interfaces

coalesce_args Decorator to "coalesce" arguments to their default values

decoratorsintrospection

HistoryDict Dictionary-like structure that tracks previous item values

tee.py Command-line program to pipe standard input into given files

regular expressionscomprehensionstext processingbinary filesargument parsingcommand line interfacesfile navigation

track_instances Track all instances of the decorated classes

classesslotsmetaclassesgeneratorsdunder methodsconstructorweak references

peekable Iterator that can peek at the next item without consuming it

classesiteration tooldunder methodsmaking iteratorsexception handling

OrderedSet (redux) Set-like object that maintains insertion-order of items

classesmaking iteratorsefficiency

make_class Class factory function

classesefficiency

lines2.py Command-line program to calculate line counts by file type

dataclassescomprehensionsgeneratorstext processingternary operatorargument parsingcommand line interfacesfile navigation

snake_case Utilities to allow "snake_case" usage in a class with "camelCase" methods

classesregular expressionsdecorators

sqlite ORM Lightweight SQLite database orm

dups.py Command-line utility for identifying duplicate files

file processingbinary filesargument parsingefficiencycommand line interfaces

class_property A combination of property decorator and classmethod decorator

classesdecoratorsdescriptors

gz Command-line program compresses (gzips) a given file

file processingbinary filesargument parsingcommand line interfaces

Vector (redux) Class representing 3-dimensional vector

classesdataclassesslotsmaking iteratorsefficiency

SuperMap Class that stores objects based on specific attribute values

classesdunder methods

split Command line program to split a file into smaller files

comprehensionsgeneratorstext processingargument parsingcommand line interfaces

OrderedDict Like collections.OrderedDict but with indexable keys

classesslotsgeneratorsdunder methodsmaking iterators

reloopable Reset iterator each time looping over a file

classescontext managersmaking iteratorsfile processingfile navigation

fancy_iterable A utility that lazily performs various operations on a given iterable

warningutils Raise exceptions when warnings are issued

classescontext managersdataclassesgeneratorsdunder methodsexception handling

dunder_all Utilities to help populate a modules' __all__ attribute

context managersintrospection

bullet points (redux) Utilities for parsing nested bullet points along with notes

classesdataclassesregular expressionscomprehensionsdunder methodstext processing

mutable_hash Function to hash common mutable types

slotsrecursionlist

replr A Python REPL that can save and restore its session state

binary filescommand line interfaces

pattern_rename2.py Program to rename files from one naming scheme to a different naming scheme

regular expressionsargument parsingcommand line interfaces

RandomNumber A class attribute that generates new data on each access

classespropertiesdescriptorsmathdunder methods

HistoryDict (redux) Dictionary-like structure that tracks previous item values

overload Decorator for function overloading (based on argument number and types)

classesdecoratorsgeneratorsexception handling

at A utility for chaining decorator functions together

decoratorsmetaclasses

fancy_enums A series of custom enumeration classes

iterable classmetaclasses

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