Ned Batchelder
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nedbat.com
Ned Batchelder
@nedbat.com
4.3K followers 170 following 220 posts
Python, Boston, mathy fun, juggling, autism parenting. https://nedbat.com
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nedbat.com
I'm writing letters to defend democracy, how are you spending your day? votefwd.org
A stack of stamped envelopes, ready for mailing
October 25, 2025 at 5:13 PM
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Every puzzle contains another puzzle: how was it constructed? The game Flow Free asks you to find the paths to connect same-colored dots on a grid. How are these layouts created?
A hexagonal grid with tightly-packed paths connecting same-colored dots.
August 7, 2025 at 5:08 PM
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Want a concise daily digest of issue and pull request activity from your GitHub repos? Try Dinghy: pypi.org/project/ding...
April 2, 2025 at 2:44 PM
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My watchgha lets you watch the progress of GitHub Actions in your terminal. Now the job names are sorted, since GitHub now returns them in a randomish order.

github.com/nedbat/watch...
March 25, 2025 at 6:41 PM
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In #Python, @classmethod can used to create alternate constructors for making objects in other ways. Here's a simple example:
An example class called Pet with an alternate constructor. Full text at https://gist.github.com/nedbat/b83352b2e20e0dc297ea99a37e172a8c
January 18, 2025 at 6:10 PM
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Comparison operators in #Python can be chained together, but using them that way could be controversial. I wrote this this other day:
Checking two variable are equal and not zero: n_passed == n_tests != 0. Full text at https://gist.github.com/nedbat/6f92fe29bdb47c0a36be0d29f5dd92ae
January 13, 2025 at 1:49 PM
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Years ago, I tried ads on my site. My business card cube page got some attention, so I had $200 revenue for the year. When my tax guy saw that, he said, "Why don't you just make 1000 sites?" He was ahead of his time...

nedbatchelder.com/text/cardcub...
Visual steps to assemble a six-card cube.
January 9, 2025 at 11:18 PM
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Wow, Apple somehow added a notification with a circle-x close button that literally does not work, and the thing appears on every video call:
"Turn On Reactions" pop-up: "Google Chrome has turned off reaction effects..." etc.
January 8, 2025 at 10:37 PM
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Happy #Python New Year!
Printing "Happy New Year 2025" with two different sums and powers using range(10). Full text at https://gist.github.com/nedbat/7eb9222bf0d3466f2bbf6381ccaf89ec
December 31, 2024 at 6:23 PM
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Is this #Python too compact? Perhaps, but there could be useful things to learn. Full explanation unpacked at nedbatchelder.com/blog/201802/...
A Python function to unpack ranges like "1-5,7,9,10-13" into a list of numbers. Full text at https://gist.github.com/nedbat/01fe96aac4a7d35bbd95e0fe9d5c6649
December 12, 2024 at 11:49 AM
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After I posted, I saw that the browser has to be nearly full-width on my laptop for it to display.
December 11, 2024 at 3:38 AM
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Splitting a string once in #Python: .split() has maxsplit=, but .partition() can be better:
Demonstrating how to split a string just once with .split(maxsplit=), and with .partition(). Full text at https://gist.github.com/nedbat/93ff430f32231361ad0910433cc2c430
December 6, 2024 at 4:40 PM
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I got a lot of replies with suggestions, so here are more #Python expressions to check if a (possibly empty) string has only 0's and 1's in it:
More Python expressions. Full text at https://gist.github.com/nedbat/d224e99e3b88a6484715cc5318e2b104
December 4, 2024 at 12:30 PM
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You can write short powerful #Python expressions using its many tools. Are there other ways to check if a string contains only "0" or "1"?
Six different Python checks of a string. Full text at https://gist.github.com/nedbat/5e7c0874df2134f101e8331d3f7c6d5c
December 1, 2024 at 4:02 PM
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Are you using #Python 3.11 yet? It's been out for two years! Maybe this will entice you: better error messages!
Showing 3.10 and 3.11 with the same error. 3.11 pinpoints the problem. Full text at https://gist.github.com/3a186827ac8bdfa08f34d36b9fce48dc
November 26, 2024 at 6:33 PM
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Classes in #Python can define their own formatting mini-languages for f-strings by defining __format__. Full details: nedbatchelder.com/blog/202204/...
A latitude/longitude class that can be formatted in various ways. Full text at https://gist.github.com/nedbat/4deeb3c4277bb29bf55bf5fb1d11b33e
November 24, 2024 at 7:14 PM
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But "charging" is still black/white with a symbol. Why take yellow from iPhone and not the rest of the design (green for charging)? This just seems dumb.
A macOS menu bar showing the battery charging with a lightning bolt symbol.
November 23, 2024 at 3:06 PM
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Who at Apple thought low-power mode in Sequoia should be represented by yellow in the all-monochrome menu bar? Yellow means low power (a good thing)? Yellow on white? wtf?
Part of the macOS menu bar with the battery level indicated by a yellow-filled rectangle.
November 23, 2024 at 1:30 PM
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What if you want space around the word before centering? Is #Python letting me take this too far? Nested f-strings!?
Adding spaces around a word before centering it in equals signs. Full text at https://gist.github.com/nedbat/fa35b505438146816851f9836fd2593c
November 22, 2024 at 5:14 PM
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Also: you can also use variables (or expressions?!) for the formatting information! #Python is cool...
More details and explanation at fstring.help
Showing using variables for the character and width specification in the format. Full text at https://gist.github.com/nedbat/db70d4cc6f16e88a33889ec113dcbe4d
November 21, 2024 at 5:50 PM
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String formatting in #Python lets you left-, right-, or center-justify a value. You can specify the fill character to use. The syntax is colon, fill-char, <^>, width:
Demonstrating string formatting with right-, left-, and center-aligned text and custom fill characters. Full text at https://gist.github.com/nedbat/9a29a7e0f8091844d65f5ca433612e59
November 21, 2024 at 11:12 AM
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For loops in #Python can assign to more than just plain names. Any assignment target is allowed:
Using `for params["page"] in ...` to move through paged results in a search API. Full text at https://gist.github.com/nedbat/d04b7d1bef5fb84542f23126424c814c
November 17, 2024 at 12:04 PM
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#Python primitives are powerful tools that can combine to get a lot done with just a little code. The dict() constructor can make a dict from key/value pairs:
dict() takes pairs, and .split() can make pairs. Combine them to parse a string of options. Full text at https://gist.github.com/0e053c8c23de3e6bc83727d3cd94240e
November 11, 2024 at 4:39 PM
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Nested loops can sometimes be replaced by one itertools.product() from the #Python stdlib:
Examples of using itertools.product, including a graphic output of occurrences of dice totals. Full text at https://gist.github.com/nedbat/92eca8c3edd1066e366c46817653ba78
November 4, 2024 at 6:14 PM
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In #Python, dicts can have tuples as keys. Consider a dict with (x,y) keys instead of nested lists for a grid. It simplifies sparse grids, "resizes" are automatic, it doesn't matter where (0,0) is, and you can use negative positions:
A dict with (x,y) keys, printed out as a 2D board. Full text at https://gist.github.com/10c1f9a412abbd1edd21c4e55bddc5eb More added to the board, without worrying about size or position. Full text at https://gist.github.com/nedbat/10c1f9a412abbd1edd21c4e55bddc5eb
October 29, 2024 at 12:45 PM