Python News Digest 2-8.11

Build a mobile app with Kivy framework, traffic sign recognizer with Keras, using Dunder methods to refine your data model and more
08 November 2019   174

Greetings! I hope your week went great! Here's new "snaky" programming news digest.

Learn how the Omer’s team found and fixed a performance regression, how to manage static files with Flask, WhiteNoise, and Amazon CloudFront, less known modules of Python standart library and more.


  • Build a Mobile App With the Kivy Python Framework

Learn how to create a mobile\desktop app with Python and the Kivy GUI framework.

  • Traffic Sign Classification With Keras and Deep Learning

Create your our 95% accuray traffic sign recognizer with Keras and Deep Learning.

  • How We Spotted and Fixed a Performance Degradation in Our Python Code

See how Omer’s team found and fixed a performance regression introduced by a switch from Celery to RQ.

  • Serving Static Files From Flask With WhiteNoise and Amazon CloudFront

Learn how to manage static files with Flask, WhiteNoise, and Amazon CloudFront.

  • Less Known Bits of the Python Standard Library

Couple of less known modules that may be useful.

  • Using Dunder Methods to Refine Your Data Model

Learn how to use this Python feature by telling of a short story.


  • LocalStack

LocalStack gives an easy-to-use test/mocking framework for developing Cloud applications.

  • Awesome Robotic Tooling

A bunch of powerful robotic resources and tools for professional robotic development with ROS in C++ and Python.

  • conrad

It helps you track conferences and meetups on your terminal!

GraalVM 19.0.3 to be Released

Along with a new update, virtual machine implementations for in JS, Python, Ruby and R received updates too
21 November 2019   62

Oracle has published the release of the universal virtual machine GraalVM 19.3.0, which supports running applications in JavaScript (Node.js), Python, Ruby, R, any languages ​​for JVM (Java, Scala, Clojure, Kotlin) and languages ​​for which the bitcode can be generated LLVM (C, C ++, Rust). Branch 19.3 is classified as long-term support (LTS) and is notable for JDK 11 support, including the ability to compile Java code into executable files (GraalVM Native Image). The project code is distributed under the GPLv2 license. At the same time, new versions of GraalVM-based implementations of the Python, JavaScript, Ruby, and R languages ​​— GraalPython, GraalJS, TruffleRuby, and FastR — have been released.

GraalVM provides a JIT compiler that can execute on-the-fly code of any scripting language in the JVM, including JavaScript, Ruby, Python, and R, and also makes it possible to run native code in the JVM, converted to LLVM bitcode. The tools provided by GraalVM include a language-independent debugger, a profiling system, and a memory allocation analyzer. GraalVM makes it possible to create combined applications with components in different languages, allowing you to access objects and arrays from code in other languages. For languages ​​based on the JVM, it is possible to create executable files compiled into machine code that can be executed directly with minimal memory consumption (memory and thread management are implemented through the connection of the Substrate VM framework).

GraalJS changes (full list):

  • Implemented the Promise.allSettled proposal. It is available in ECMAScript 2020 mode (--js.ecmascript-version=2020).
  • Implemented the nullish coalescing proposal. It is available in ECMAScript 2020 mode (--js.ecmascript-version=2020).
  • Updated ICU4J library to version 64.2.

GraalPython changes (full list):

  • Implement gc.{enable,disable,isenabled} as stubs
  • Implement charmap_build function
  • Implement hexversion in sys module

TruffleRuby changes (full list):

  • Compilation of C extensions is now done with an internal LLVM toolchain producing both native code and bitcode. This means more C extensions should compile out of the box and this should resolve most linker-related issues.
  • It is no longer necessary to install LLVM for installing C extensions on TruffleRuby.
  • It is no longer necessary to install libc++ and libc++abi for installing C++ extensions on TruffleRuby.

 And FastR chages (full list):

  • In this release, FastR does not ship with GCC runtime libraries. Use the following commands to install the necessary dependencies:
  • Preview of support for LLVM based execution of R native extensions
  • Fixed memory leaks reported on GitHub