#65 Speed of your import statements affecting performance?
Python Bytes - Podcast tekijän mukaan Michael Kennedy and Brian Okken - Maanantaisin
Kategoriat:
Sponsored by Rollbar: pythonbytes.fm/rollbar
Brian #1: pygal : Simple Python Charting
- Output SVG or PNG
- Example Flask App (also django response) part of documentation.
- Enough other bits of doc to get you a chart in a web page super fast.
Michael #2: Thoughts on becoming a self-taught programming
- Basic format:
- I'm 31 days into self-studying Python and am loving every minute of it!
- A few questions:
- What were you doing before you began self-studying programming?
- What made you want to study programming on your own?
- How did you start (which resources and language)?
- How long did it take for you to feel confident enough in your skills and knowledge to know you could be employed as a programmer?
- What else did you do besides self-study that helped you in your journey to becoming a programmer?
- What's next for you?
Brian #3: How to speed up Python application startup time (timing imports in 3.7)
- Python 3.7 includes
-X importtime
option that allows you to profile the time it takes to do all the imports. - Way cool tool to help optimize the startup time of an application.
Michael #4: AnPyLar - The Python web front-end framework
- Create web applications with elegance, simplicity and yet full power with Python and components
- MISSION: Empower all Python programmers to work not only on the back-end but also on the front-end with the same language of choice
- Features
- Reactive programming and Promises
- Python standard formatting as templates
- reusable components
- Scoped styling for component
- Integrated routing engine
Brian #5: Migrating to Python 3 with pleasure
- “A short guide on features of Python 3 for data scientists”
- Quick tutorial through examples of
pathlib
. - Type hinting and how cool it works with editors (PyCharm example shown)
- Adding runtime type enforcement for specific methods using enforce
- Using function annotations for units, as done in astropy.
- Matrix multiplication with
@
. - Globbing with
**
.found_images = glob.glob('/path/**/*.jpg', recursive=True)
- Also … underscores in numeric literals, f-strings, true division with
/
, integer division with//
, and lots of more fun goodies.
Michael #6: Moving to Python 3
- Many of these issues were corrected just by running 2to3, which not only fixed many of the compatibility issues
- Outdated external libraries which needed to be updated to newer versions featuring Python 3 compatibility
basestring
tostr
,urlparse
tourllib.urlparse
and similar major changes - Dictionary change like
iteritems()
toitems()
, or.items()
now returning a view. - Things that weren't needed anymore, like Django's
force_unicode
or__future__
library tools.
- Outdated external libraries which needed to be updated to newer versions featuring Python 3 compatibility
- Once we finished working on the "low-hanging fruits", the next step was to run Aphrodite's test suite and achieve zero errors.
- Lessons learned
- Code coverage was originally around 70%,
- Keeping the Python 3 branch up to date with master
- A non-trivial feature was delivered during the migration (via feature branch)
- The pickle protocol version in python 3 can be higher than the highest available in Python 2.7. So we needed to add versioning to our Django caches
- Each modified file had to comply with flake8 linting rules
- Afrodita is currently running on Google App Engine Flexible, and one of the features our team loves with is traffic splitting
- With this feature, we can do canary releases with ease: We just deploy our new version of the service, and start redirecting small amounts of traffic traffic while we monitor for unexpected errors.
- After some minor bugfixes, we could bring the traffic of the Python 3.6 version to 100% with confidence. We also had the old version available for instant rollback, thanks to how parallel versions and traffic splitting work in GAE flexible.
Our news
Brian:
- Upcoming webinar: Productive pytest with Pycharm
Michael:
- My GUI example: https://github.com/mikeckennedy/pyramid-web-builder-python-gui