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#222: Autocomplete with type annotations for AWS and boto3

Published Wed, Feb 24, 2021, recorded Wed, Feb 24, 2021

Sponsored by Linode!

Special guest: Greg Herrera

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Michael #1: boto type annotations

  • via Michael Lerner
  • boto3's services are created at runtime
  • IDEs aren't able to index its code in order to provide code completion or infer the type of these services or of the objects created by them.
  • Type systems cannot verify them
  • Even if it was able to do so, clients and service resources are created using a service agnostic factory method and are only identified by a string argument of that method.
  • boto3_type_annotations defines stand in classes for the clients, service resources, paginators, and waiters provided by boto3's services.

Example with “bare” boto3:

Example with annotated boto3:

Brian #2: How to have your code reviewer appreciate you

  • By Michael Lynch
  • Suggested by Miłosz Bednarzak
  • Actual title “How to Make Your Code Reviewer Fall in Love with You”
    • but 🤮
    • even has the words “your reviewer will literally fall in love with you.”
    • literally → figuratively, please
  • Topic is important though, here are some good tips:
    • Review your own code first
      • “Don’t just check for mistakes — imagine reading the code for the first time. What might confuse you?”
    • Write a clear change list description
    • “A good change list description explains what the change achieves, at a high level, and why you’re making this change.”
    • Narrowly scope changes
    • Separate functional and non-functional changes
    • This is tough, even for me, but important.
    • Need to fix something, and the formatting is a nightmare and you feel you must blacken it. Do those things in two separate merge requests.
    • Break up large change lists
    • A ton to write about. Maybe it deserves 2-3 merges instead of 1.
    • Respond graciously to critiques
    • It can feel like a personal attack, but hopefully it’s not.
    • Responding defensively will only make things works.

Greg #3: REPODASH - Quality Metrics for Github repositories

  • by Laurence Molloy
  • Do you maintain a project codebase on Github?
  • Would you like to be able to show the maturity of your project at a glance?
  • Walk through the metrics available
  • Use-case

Michael #4: Extra, extra, extra, extra, hear all about it

  1. docker context create remotedocker --docker "host=ssh://user@server"
  2. docker context use remotedocker
  3. docker run -it ubuntu:latest bash now works as usual but remotely!
  • Why I keep complaining about merge thing on dependabot. Why!?! ;)

  • Anthony Shaw wrote a bot to help alleviate this a bit. More on that later.

Brian #5: testcontainers-python

  • Suggested by Josh Peak
  • Why mock a database? Spin up a live one in a docker container.
  • “Python port for testcontainers-java that allows using docker containers for functional and integration testing. Testcontainers-python provides capabilities to spin up docker containers (such as a database, Selenium web browser, or any other container) for testing.”

    import sqlalchemy
    from testcontainers.mysql import MySqlContainer
    with MySqlContainer('mysql:5.7.32') as mysql:
            engine = sqlalchemy.create_engine(mysql.get_connection_url())
            version, = engine.execute("select version()").fetchone()
            print(version)  # 5.7.32
  • The snippet above will spin up a MySql database in a container. The get_connection_url() convenience method returns a sqlalchemy compatible url we use to connect to the database and retrieve the database version.

Greg #6: The Python Ecosystem is relentlessly improving price-performance every day

  • Python is reaching top-of-mind for more and more business decision-makers because their technology teams are delivering solutions to the business with unprecedented price-performance.
  • The business impact keeps getting better and better.
  • What seems like heavy adoption throughout the economy is still a relatively small-inroad compared to what we’ll see in the future. It’s like water rapidly collecting behind a weak dam.
  • It’s an exciting time to be in the Python world!



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56 Funny Code Comments That People Actually Wrote: These are actually in a code base somewhere (a sampling):

     * Dear Maintainer
     * Once you are done trying to ‘optimize’ this routine,
     * and you have realized what a terrible mistake that was,
     * please increment the following counter as a warning
     * to the next guy.
     * total_hours_wasted_here = 73
    // sometimes I believe compiler ignores all my comments
    // drunk, fix later
    // Magic. Do not touch.
    /*** Always returns true ***/
    public boolean isAvailable() {
        return false;

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