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Special guest: Chris Patti
Brian #1: Using cog to update --help in a Markdown README file
- Simon Willison
- I’ve wanted to have a use case for Ned Batchelder’s cog
- Cog is a utility that looks for specially blocks
- These block can be in comments,
[HTML_REMOVED] for markdown.
- When you run cog on a file, it runs the “some code” and puts the output after the middle
]]] and before the
- Simon has come up with an excellent use, running
--help and capturing the output for a
README.md file for a CLI project.
- He even wrote a test, pytest of course, to check if the README.md needs updated.
Michael #2: An oral history of Bank Python
- Bank Python implementations are effectively proprietary forks of the entire Python ecosystem which are in use at many (but not all) of the biggest investment banks.
- The first thing to know about Minerva is that it is built on a global database of Python objects.
- Barbara is a simple key value store with a hierarchical key space. It's brutally simple: made just from pickle and zip.
- Applications also commonly store their internal state in Barbara - writing dataclasses straight in and out with only very simple locking and transactions (if any).
- There is no filesystem available to Minerva scripts and the little bits of data that scripts pick up has to be put into Barbara.
- Barbara also has some "overlay" features:
# connect to multiple rings: keys are 'overlaid' in order of
# the provided ring names
db = barbara.open("middleoffice;ficc;default")
# get /Etc/Something from the 'middleoffice' ring if it exists there,
# otherwise try 'ficc' and finally the default ring
some_obj = db["/Etc/Something"]
- Lots of info about modeling with classes (instruments, books, etc)
- If you understand excel you will be starting to recognize similarities.
- In Excel, spreadsheets cells are also updated based on their dependencies, also as a directed acyclic graph. Dagger allows people to put their Excel-style modelling calculations into Python, write tests for them, control their versioning without having to mess around with files like CDS-OF-CDS EURO DESK 20180103 Final (final) (2).xlsx.
- Dagger is a key technology to get financial models out of Excel, into a programming language and under tests and version control.
- Time to drop a bit of a bombshell: the source code is in Barbara too, not on disk. Remain composed. It's kept in a special Barbara ring called sourcecode.
- Interesting table structures, like Pandas, but closer to a DB (MnTable)
- Over time the divergence between Bank Python and Open Source Python grows. Technology churns on both sides, much faster outside than in of course, but they do not get closer.
- Minerva has its own IDE - no other IDEs work if you keep your source files in a giant global database.
- What I can't understand is why it contains its own web framework. Investment banks have a one-way approach to open source software: (some of) it can come in, but none of it can go out
- BTW, I “read” this with naturalreaders app
Chris #3: Pyxel
- Pyxel is a ‘retro gaming console’ written in Python!
- This might seem old and un-shiny, but the restrictions imposed by the environment gift simplicity
- Vastly decreased learning time and effort compared to something like Unity or even Pygame
- Straight forward simple commands, just like it was for micro-computers in the 80s
- cls(), line(), rect(), circ() etc.
- Pyxel is somewhat more Python and less console than others like PICO-8 or TIC-80 but this is a feature! Use your regular development environment to build.
Brian #4: How to Ditch Codecov for Python Projects
- Hynek Schlawack
- Codecov is a third party service that checks your coverage output and fails a build if coverage dropped.
- It’s not without issues.
- Hynek is using coverage.py
--fail-under flag in place of this in GitHub actions.
- It’s not as simple as just adding a flag if you are using
--parallel to combine coverage for multiple test runs into one report.
- Hynek is utilizing the coverage output as an artifact for each test, then pulling them all together in a
coverage stage combine and check coverage.
- He provides the snippet of GH Action, and even links to a working workflow file using this process. Nice!
Michael #5: tiptop (like glances)
- via Zach Villers
- tiptop is a command-line system monitoring tool in the spirit of top. It displays various interesting system stats, graphs it, and works on all operating systems.
- Really nice visualization for your servers
- Good candidate for pipx install tiptop
Chris #6: pyc64
- A Commodore 64 emulator written in pure Python!
- Not 100% complete - screen drawing is PETSCII character mode only
- This still allows for a lot of interesting apps & exploration
- Actual machine emulation using py65 - a pure Python 6502 chip emulator!
- You can pop to a Python REPL from inside the emulator and examine data structures like memory, registers, etc!
- An incredible example of what Python is capable of
- 0.6 Mhz with CPython and over 2Mhz with pypy!
Joke: I hate how the screens get bright so early this time of year