#273: Getting dirty with eq(self, other)

Published Fri, Mar 4, 2022, recorded Tue, Mar 1, 2022

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Michael #1: Physics Breakthrough as AI Successfully Controls Plasma in Nuclear Fusion Experiment

Interesting break through using AI
Is Python at the center of it?
With enough digging, the anwswer is yes, and we love it!

Brian #2: PEP 680 -- tomllib: Support for Parsing TOML in the Standard Library

Accepted for Python 3.11
This PEP proposes basing the standard library support for reading TOML on the third-party library tomli

Michael #3: Thread local

threading.local: A class that represents thread-local data. Thread-local data are data whose values are thread specific.
Just create an instance of local (or a subclass) and store attributes on it
You can even subclass it.

Brian #4: What is a generator function?

Trey Hunner
Super handy, and way easier than you think, if you’ve never written your own.
Really, it’s just a function that uses yield instead of return and supplies one element at a time instead of returning a list or dict or tuple or other large structure.
Some details
- generator functions return generator objects
- generator objects are on pause and use the built in next() function to get next item.
- they raise StopIteration when done.
- Most generally used from for loops.
- Generator objects cannot be re-used when exhausted
  - but you can get a new one with the next for loop you use. So, it’s all good.

Michael #5: dirty-equals

via Will McGugan, by Samual Colvin
Doing dirty (but extremely useful) things with equals.
```
from dirty_equals import IsPositive
```

assert 1 == IsPositive assert -2 == IsPositive # this will fail!

  user_data = db_conn.fetchrow('select * from users')
  assert user_data == {
       'id': IsPositiveInt, 
       'username': 'samuelcolvin', 
       'avatar_file': IsStr(regex=r'/[a-z0-9\-]{10}/example\.png'), 
       'settings_json': IsJson({'theme': 'dark', 'language': 'en'}), 
       'created_ts': IsNow(delta=3), 
   }

Brian #6: Commitizen

from the docs
- Command-line utility to create commits with your rules. Defaults: Conventional commits
- Display information about your commit rules (commands: schema, example, info)
- Bump version automatically using semantic versioning based on the commits. Read More
- Generate a changelog using Keep a changelog
considering using for consistent commit message formatting
can be used with python-semantic-release for automatic semantic versioning
learned about it in 10 Tools I Wish I Knew When I Started Working with Python
questions
- anyone using this or something similar?
- does this make sense for small to medium sized projects? or overkill?

Extras:

pytest book
- 40% off sale continues through March 19 for eBook
- Amazon lists the book as “shipping in 1-2 days”, as of March 2

Michael:

Pronouncing the Python Walrus operator := as “becomes”
Via John Sheehan: String methods startswith() and endswith() can take a tuple as its first argument that lets you check for multiple values with one call:
```
    >>> x = "abcdefg"
    >>> x.startswith(("ab", "cd", "ef"), 2)
    True
```

Joke: CS Background

Want to go deeper? Check our projects

Course: Python for the Absolute Beginner course

Beginners

HTMX + Flask

FastAPI

pytest book

Full transcript

#273: Getting dirty with __eq__(self, other)

Want to go deeper? Check our projects

#273: Getting dirty with eq(self, other)