#134 Python proves Mercury is the closest planet to Earth

Python Bytes - A podcast by Michael Kennedy and Brian Okken - Lunedì

Brian #1: Three scientists publish a paper proving that Mercury, not Venus, is the closest planet to Earth. using Python

contributed by, and explained by, listener Andrew Diederich.

“This is from the March 19th, 2019 Strange Maps article. Which planet is, on average, closest to the Earth? Answer: Mercury. Actually, Mercury is, on average, the closest to all other planets, because it’s closest to the sun.”
article, including video, uses PyEphem, which apparently is now deprecated and largely replaced with skyfield.

Michael #2: Github semantics

Parsing, analyzing, and comparing source code across many languages
Written in a Haskell, it’s a library and command line tool for parsing, analyzing, and comparing source code.
It’s still early days yet, but semantic can do a lot of cool things, and is powering public-facing GitHub features. I’m tremendously excited as to see how it’ll evolve now that it’s a community-facing project.
Understands: Python, TypeScript, JavaScript, Ruby, Go, …
here are some cool things inside it:
- A flow-sensitive, caching, generalized interpreter for imperative languages
- An abstract interpreter that generates scope graphs for a given program text
- A strategic rewriting system based on recursion schemes for open syntax terms

Brian #3: flake8-black

Contributed by Nathan Clayton
“The point of this plugin is to be able to run black --check ... from within the flake8 plugin ecosystem.”
I like to run flake8 during development both to keep things neat, and to train myself to just write code in a more standard way. This is a way to run black with no surprises.

Michael #4: Python Preview for VS Code

You write Python code (script style mostly), it creates an object-visualization
Think of a picture your first year C++ CS prof might draw. This extension does that automatically as you write Python code
Looks to be based (conceptually) on Philip Guo’s Python Tutor site.

Brian #5: Create and Publish a Python Package with Poetry

John Franey
Walks through creating a package, customizing the pyproject.toml, and talks about the different settings in the toml and what it means.
Then using the testpypi, and finally publish.

Michael #6: Pointers in Python: What's the Point?

by Logan Jones
Quick question: Does Python have pointers (outside of C-extensions, etc of course)?
Yet Python is more pointer heavy than most languages (more so than C# more so than even C++)!
In Python, everything is an object, even numbers and booleans.
Each object contains at least three pieces of data:
- Reference count
- Type
- Value
Check that you have the same object is instead of ==
Python variables are pointers, just safe ones.
Interesting little tidbit from the article:
- Interning strings is useful to gain a little performance on dictionary lookup—if the keys in a dictionary are interned, and the lookup key is interned, the key comparisons (after hashing) can be done by a pointer compare instead of a string compare. (Source)
But like we have inline-assembly in C++ and unsafe mode in C#, we can use pointers in Cython or more fine-grained with ctypes.

Extras

Michael:

PSF needs your help. Spread the word about the fundraiser and please, ask your company to contribute: Building the PSF: the Q2 2019 Fundraiser (Donations are tax-deductible for individuals and organizations that pay taxes in the United States)
- “Contributions help fund workshops, conferences, pay meetup fees, support fiscal sponsorships, PyCon financial aid, and development sprints. ”

Jokes

via Jay Miller

What did the developer name his newborn boy? JSON