Photo credits

All photographs on Four Spaces are in the public domain or released under the Creative Commons CC0 dedication, and were found on Wikimedia Commons. Several are works of the US federal government (National Archives, US Army, NASA, Census Bureau, Department of Defense) or come from the Library of Congress. Each image was resized and cropped to a 3:2 format and converted to WebP; no other changes were made. No image, logo or graphic from the former website on this domain has been used.

The pictures of compositors, typists and punch-card operators stand in for the subject of an article. None of the people or places shown has any link with Four Spaces, and none of them endorses it.

Photos by page

• A Code Review Checklist for Python Projects: Students in a late nineteenth-century printing shop standing at slanted type cases, setting type by hand. Photo: Frances Benjamin Johnston, Compositors working in printing shop, Hampton Institute, Hampton, Virginia LCCN94502417.jpg (Wikimedia Commons), Public domain.
• Adopting PEP 8 and a Formatter in an Existing Python Codebase: The United States Capitol seen across a wide lawn, with scaffolding on part of its facade during renovation. Photo: US Department of Defense, Defense Visual Information Center, A view of the United States Capitol building with scaffolding erected for exterior renovation - DPLA - 84e6200a7aa20c27adc9180a8cc915d9.jpeg (Wikimedia Commons), Public domain.
• Black, the Python Code Formatter: How It Works and How to Configure It: An engraving of a two-handled printer's composition roller used for inking type. Photo: American Type Founders Co., 1906 ATF composition hand roller.jpg (Wikimedia Commons), Public domain.
• How to Check Python Code Style Locally with pycodestyle, flake8 and ruff: A young woman in a 1940s office operating a card punch machine, a stack of punched cards beside her. Photo: Unknown photographer, US National Archives, Card puncher - NARA - 513295.jpg (Wikimedia Commons), Public domain.
• PEP 8 Explained: The Python Style Guide, Section by Section: A long workshop hall filled with rows of nineteenth-century printing presses and their levers. Photo: Mathew Benjamin Brady (attributed), US National Archives, Printing presses at Bureau of Engraving and Printing - NARA - 530059.jpg (Wikimedia Commons), Public domain.
• PEP 8 Programming Recommendations: is None, Bare except, Lambdas and Other Habits: A cluttered bicycle workshop with a wheel on a truing stand, spare parts on the bench and tools hanging on a pegboard. Photo: Foxtod, Bicycle wheel truing stand.jpg (Wikimedia Commons), CC0.
• Pre-commit Hooks for Python: Run Linters and Formatters Before Every Commit: Sepia photograph of the inside of a wooden railway signal box, with a long row of signal levers under tall windows. Photo: Unknown photographer, Bundamba railway station signal box.jpg (Wikimedia Commons), Public domain.
• Python Docstrings: PEP 257 Conventions, Formats and Tools: A dark grey museum wall label with a printed introduction text about devotional paintings and altarpieces. Photo: BurgererSF, Introduction label NMW.jpg (Wikimedia Commons), CC0.
• Python Imports Style: Order, Grouping, Absolute vs Relative and Wildcards: Aerial view of a large container port with green gantry cranes and long rows of stacked shipping containers. Photo: Brian Harris, US Army, Aerial view of shipping containers, and big container cranes at Tacoma's container port -a.jpg (Wikimedia Commons), Public domain.
• Python Indentation and Line Length: 4 Spaces, 79 Characters and Continuation Lines: Rows of students typing on heavy manual typewriters in a high-school classroom, with a blackboard behind them. Photo: National Photo Company Collection, Library of Congress, Eastern High, Typewriting class, (Washington, D.C.) LCCN2016824250.jpg (Wikimedia Commons), Public domain.
• Python Naming Conventions: Modules, Classes, Functions, Constants and Underscores: Two green street name signs, SE Nye Av and SE 3rd Dr, mounted on a pole above the back of a stop sign under a grey sky. Photo: Roc0ast3r, Street signs on the intersection of SE Nye Avenue and SE 3rd Drive (2024) - 0707.jpg (Wikimedia Commons), CC0.
• Python Type Hints: From PEP 484 to Modern Syntax, with Style Rules: A single red jigsaw puzzle piece lying on top of a heap of green pieces on a wooden table. Photo: Profpcde, Red jigsaw puzzle piece on green pieces.jpg (Wikimedia Commons), CC0.
• Readable Python Code: Beyond PEP 8: Rows of students reading at long desks in the Library of Congress reading room, around 1900, with marble columns behind. Photo: Frances Benjamin Johnston, Students in the Reading Room of the Library of Congress with the Librarian of Congress, Herbert Putnam, watching LCCN98502945.jpg (Wikimedia Commons), Public domain.
• Relocating as a Software Developer: A Practical Checklist for Your First Months in a New City: A mover in a blue T-shirt and face mask tapes up a tall cardboard box in an apartment, with more boxes on the floor. Photo: Lisa Bishop, US Army, Stay safe during moving of household goods (6222155).jpg (Wikimedia Commons), Public domain.
• Ruff for Python: Linter and Formatter, Rule Selection and Configuration: A man and a woman working at the control console and tape units of an IBM 704 computer in a 1950s machine room. Photo: NASA, IBM Electronic Data Processing Machine - GPN-2000-001881.jpg (Wikimedia Commons), Public domain.
• Whitespace and Blank Lines in Python: What PEP 8 Asks For: Compositors in shirtsleeves standing at tall wooden type cases in a newspaper composing room, early 1900s. Photo: Svenska Dagbladet, Case department at SvD.jpg (Wikimedia Commons), Public domain.
• Writing Useful Comments in Python: What PEP 8 Says and What Helps Readers: Close-up of a medieval handwritten manuscript page in brown ink, with notes squeezed into the margin of the facing page. Photo: Basel University Library (scan), Basel, Universitätsbibliothek, A VII 42, f. 103r – Composite manuscript theological content.JPG (Wikimedia Commons), Public domain.
• flake8 and pylint: What Each Python Linter Checks and How They Differ: Rows of women at keypunch machines in a large 1940s office, transferring census forms onto punched cards. Photo: US Census Bureau, Keypunching 1940s census.jpg (Wikimedia Commons), Public domain.
• pycodestyle Error Codes Explained: E1 to E9 and W1 to W6: Uniformed women telephone operators wearing headsets work side by side at a large switchboard. Photo: Unknown photographer, US National Archives, WAC telephone operators operate the Victory switchboard during the Potsdam Conference in their headquarters in... - NARA - 199007.jpg (Wikimedia Commons), Public domain.

Typefaces

Bitter (Huerta Tipográfica), Red Hat Text and Red Hat Mono (Red Hat, Inc., designed with MCKL), all under the SIL Open Font License 1.1, served from this site.

Style checker

The checker on the home page is original code written for Four Spaces. Its rules and messages follow those of pycodestyle, which is distributed under the MIT ("Expat") licence.