Tuesday, June 24, 2025

Getting a hysterectomy: My reasons and recovery

Back in 2014, I had a brush with cervical cancer. We fortunately caught it when it was stage 0, the point at which it's not even called cancer, and is called adenocarcinoma instead. I went in for surgery, a procedure called cervical conization, where the doctor basically scrapes the potentially cancerous area out of the cervix and then biopsies the remaining cells to make sure they caught all the sketchy cells.

After the surgery, the doctor told me, "I tried to leave enough cervix for you to have children naturally in the future, but call us when you're done having kids so we can schedule you for a hysterectomy." Apparently, the best way to reduce the risk of future cervical cancer is to remove the cervix entirely, along with the nearby fallopian tubes and uterus. That was really jarring to hear at the time, because I wasn't even close to having kids - I wasn't emotionally ready to be a mom, nor was I in a relationship that was at a settling down point - and I could already feel the doctors eye'ing my reproductive organs for removal.

Well, 11 years later, the doctors finally got their wish (aka, my organs)! I met my partner 7 years ago, we decided to have kids, and I popped out one daughter in 2019 and our second in 2021. After every birth, my doctor would ask if I was ready to stop having kids. We both originally considered having 3 kids, but by the time the second daughter was 2 years old, I realized I was personally ready to say goodbye to my baby-making days. Why?

The Reasons

  • Pregnancy is really rough. The first pregnancy, I was awed by my body's ability to mutate into a womb-carrying machine, and that was enough distraction from the extreme bodily discomfort. By the second pregnancy, I was over it. I had "morning sickness" most of the first trimester, to the point that I actually lost weight due to my general disgust around food. I was so tired to the point that I qualified as "clinically depressed" (I really like having energy to do things, so I get depressed when I realized I don't have energy to do anything). I had more energy and less nauseu in the second and third trimesters, but then I was just constantly annoyed that my massive belly made it impossible for me to do my favorite things, like biking and cartwheels. And then, there's labor! But let's not get into the details of why that sucked.. at least, that only lasts a few days and not 9 months.
  • Breastfeeding is boring and injurious. I ended up breastfeeding both my kids for two years, as it somewhat worked logistically, and seemed easier than formula in some ways (no bottle prep). However, I did not find it to be a magical mommy-baby bonding experience. It was just my body being used as a vending machine for very hungry babies for up to 10 hours a day, and me trying to find a way to bide my time while they got their nutrients. I eventually found ways to fill the boredom, thanks to my nursing-friendly computer setups, but I then got multiple nursing-related injuries with the second daughter. I will not detail them here, but once again… rough! If I did have a third, I would consider formula more seriously,, but I fear my inner DIY-er would guilt me into breastfeeding once again.
  • I am outnumbered. Two daughters, one of me. I can't make them both happy at the same time. I am constantly referee'ing, trying to make calls about whose toy is whose, who hit who first, who really ought to share more, whose turn it is to talk. It is exhausting. When both my partner and I are taking care of them, we can divide and conquer, but if we had a third: we would *always* be outnumbered.
  • Transportation logistics. We have two car seats in our Forester, we can't fit a third. I have only two seats on my e-bike, I can't fit a third kid. I have a two-kid wagon. I have two hands for holding hands while walking. Etc, etc! Two kids fit pretty well, three kids would require refactoring.
  • I like having my bodily autonomy back. It was such a great feeling when I finally stopped being pregnant/nursing and could start making decisions solely to benefit my body, without worrying about the effect on children. I stopped feeling so ravenously hungry all the time, and rapidly dropped the 40 pounds I'd gained from motherhood. I could finally rid my feet of a pregnancy-induced 5-year-duration fungus (I know, gross!) with an oral antifungal that I wasn't allowed to take while pregnant/nursing. It is absolutely amazing that women give their bodies up in order to propagate the human race, but it's also amazing when we get to take control of our bodies again.
  • Housing logistics. We have a 2-bedroom house in the bay area. Our two daughters are currently sharing a room (somewhat happily?) and my partner and I share a room (happily). If we had a third kid, we'd likely have to divide up our house somehow, or move houses. Doable, but not trivial.
  • I love my kids. I want to end with this reason to make something clear: My daughters are lovely, creative, hilarious, souls! I am thankful that I was able to bring them into the world, and witness their growth into little humans. By keeping our family smaller, I'll be able to spend more time with them going forward, and not be distracted by new additions. I look forward to many adventures!

The Surgery

Once I was feeling totally certain of the decision, about 6 months ago, I notified my doctor. It took some time before the surgery could actually happen, since I needed to find a time that worked around my work obligations and was free in the doctor's schedule. In the meantime, we discussed exactly what kind of hysterectomy I would get, since there are multiple reproductive organs that can be removed.

What we decided:

Organ Notes Decision
Cervix Obviously, this was on the chopping block, due to it being the site of pre-cancer before. 🔪Remove!
Uterus The uterus is only needed if having more babies, and multiple cancers can start in the uterus. 🔪Remove!
Fallopian tubes These also typically get removed, as ovarian cancer often starts in the tubes (not the ovaries, confusingly). I had a grandmother who got ovarian cancer twice, so it seems helpful to remove the organs where it likely started. 🔪Remove!
Ovaries This was the trickiest decision, as the ovaries are responsible for the hormonal cycle. When a hysterectomy removes the ovaries, that either kicks off menopause early or, to avoid that, you have to take hormones until the age you would naturally start menopause (10 years, for me). Apparently both early menopause and the hormone treatment are associated with other cancers/illnesses, so my doctor recommended keeping the ovaries. 🥚Keep!

Getting rid of three organs seems like kind of a big deal, but the surgery can be done in a minimally invasive way, with a few incisions in the abdomen and a tiny camera to guide the surgeon around. It's still a major surgery requiring general anesthesia, however, which was what worried me the most: what if I never woke up?? Fortunately, my best friend is an anesthesiologist at Johns Hopkins and she told me that I'm more likely to be struck by lightning.

My surgery was scheduled for first thing in the morning, so I came in at 6am, got prepped by many kind and funny nurses, and got wheeled into the OR at 8am. The last thing I remember was the anesthesiologist telling me something, and then boom, five hours later, I awoke in another room.


The Recovery

Upon first waking, I was convinced that balloons were popping all around me, and I kept darting my eyes around trying to find the balloons. The nurse tried to reassure me that it was the anesthesia wearing off, and I both totally believed her, but also very much wanted to locate the source of the balloon popping sounds. 👀 🎈

Once the popping stopped, she made sure that I was able to use the bathroom successfully (in case of accidental bladder injury, one of the hysterectomy risks), and then I was cleared to go home! I got home around 2pm, and thus began my recovery journey.

I'll go through each side effect, in order of disappearance.

Fatigue (Days 1 + 2)

That first day, the same day that I actually had the surgery, I was so very sleepy. I could not keep my eyes open for more than an hour, even to watch an amazing spiderman movie (the multiverse). I slept most of the rest of that day.

The second day, I felt sleepy still, but never quite sleepy enough to nap. I would frequently close my eyes and see hypnagogic visions flutter by, and sometimes go lie in my bed to just rest.

The third day, I felt like I had my energy back, with no particular sleepiness.

Nausea (Days 1 + 2)

I was warned by the anesthesiologist that it was common to experience nausea after general anesthesia, especially for women of my age, so they preemptively placed a nausea patch behind my ear during the surgery. The nausea patch has some funky side effects, like double vision that meant I couldn't look at text on a computer screen for more than a few minutes. I missed being able to use a computer, so I took off the patch on the second night. By the next morning, my vision was restored and I was able to code again!

Abdominal soreness (Days 1-5)

My doctor warned me that I would feel like "you've just done 1000 crunches". I did feel some abdominal soreness/cramping during the first few days, but it felt more like… 100 crunches? It probably helped that I was on a regular schedule of pain medicine: alternating between Ibuprofen and Tylenol every 3 hours, plus Gabapentin 3 times a day. I also wore an abdominal binder the first few days, to support the abdominal muscles. I never felt like my pain was strong enough to warrant also taking the narcotic that they gave me, and I'm happy that I avoided needing that potentially addictive medicine.

There was one point on Day 5 where I started cracking up due to a stuck-peach-situation at the grocery store, and I tried to stop laughing because it hurt so bad… but gosh darn we just couldn't rescue that peach! Lessons learned: don't laugh while you're in recovery, and do not insert a peach into a cupholder that's precisely the same radius as the peach. 🍑

Collarbone soreness (Days 4-6)

My collarbone hurt more than my abdomen, strangely enough. I believe that's due to the way they inflate the torso with gas during the surgery, and the after-effects of that gas on the upper part of the torso. It weirded me out, but it was also a fairly tolerable pain.

Sore throat (Days 1-7)

This was the most surprising and persisting side effect, and it was due to the breathing tube put down my throat during general anesthesia. Apparently, when a surgery is long enough, the patient gets intubated, and that can make your throat really sore after. I couldn't even read a single story to my kids the first few days, and it took me a good week to feel comfortable reading and speaking again. During that week, I drank Throat Coat tea with honey, gargled warm water, sucked on lozenges - anything to get my voice back! It's a good thing that I didn't have to give any talks the week after, as I doubt my voice would have made it through 60 minutes of continuous use.

Surgical wounds (Days 1 - ?)

The doctor made four cuts on my abdomen: one sneaky cut through the belly button, and three other cuts a few inches away from it. They sealed the cuts with liquid glue, which made them look nastier and bigger than they actually were, due to the encrusted blood. The wounds were only painful when I prod at them from particular angles, or more accurately, when my toddler prodded at them from particularly horrible angles.

By Day 18, the liquid glue had came off entirely, revealing scars about 1/2 inch in length. Only the belly button wound still had a scab. According to my doctor, the belly button wound is the most likely to get infected or herniate and takes the longest to heal. Go go gadget belly button!

Activity restrictions (Days 1 - ?)

I stopped taking medicines on day 6, as I didn't feel any of my symptoms warranted medication, and I was generally feeling good. However, I still have many restrictions to ensure optimal healing.

My only allowed physical activity is walking - and I've been walking up the wazoo, since everyone says it helps with recovery. I'm averaging 7K steps daily, whereas I usually average 4K steps. I've realized from this forced-walking experience that I really need to carve out daily walking opportunities, given that I work from home and can easily forget to walk any steps at all. Also, walking is fun when it gives me an excuse to observe nature!

I'm not allowed other physical activity, like biking or yoga. Plus, my body can't be submerged in water, so no baths or swimming. Worst of all: I'm not allowed to lift objects > 20 pounds, which includes my toddler! That's been the hardest restriction, as I have to find other ways to get her into her car seat, wagon, toilet, etc. We mostly play at home, where I can avoid the need for lifting here.

At my 6-week post-op appointment, my doctor will evaluate me in person and hopefully remove all my activity restrictions. Then I'll bike, swim, and lift children to my heart's content! 🚴🏻‍♀️ 🏊🏻 🏋🏼‍♀️

Monday, June 23, 2025

Proficient Python: A free interactive online course

There are many ways to learn Python online, but there are also many people out there that want to learn Python for multiple reasons - so hey, why not add one more free Python course into the mix? I'm happy to finally release ProficientPython.com, my own approach to teaching introductory Python.

The course covers standard intro topics - variables, functions, logic, loops, lists, strings, dictionaries, files, OOP. However, the course differs in two key ways from most others:

  • It is based on functions from the very beginning (instead of being based on side effects).
  • The coding exercises can be completed entirely in the browser (no Python setup needed).

Let's explore those points in more detail.

A functions-based approach

Many introductory programming courses teach first via "side effects", asking students to either print out values to a console, draw some graphics, manipulate a webpage, that sort of thing. In fact, many of my courses have been side-effects-first, like my Intro to JS on Khan Academy that uses ProcessingJS to draw pictures, and all of our web development workshops for GirlDevelopIt. There's a reason that it's a popular approach: it's fun to watch things happen! But there's also a drawback to that approach: students struggle when it's finally time to abstract their code and refactor it into functions, and tend not to use custom functions even when their code would benefit from them.

When I spent a few years teaching Python at UC Berkeley for CS61A, the first course in the CS sequence, I was thrown heads-first into the pre-existing curriculum. That course had originally been taught 100% in Scheme, and it stayed very functions-first when they converted it to Python in the 2000s. (I am explicitly avoiding calling it "functional programming" as functional Python is a bit more extreme than functions-first Python.) Also, CS61A had thousands of students, and functions-based exercises were easier to grade at scale - just add in some doctests! It was my first time teaching an intro course with a functions-first approach, and I grew to really appreciate the benefits for both student learning and classroom scaling.

That's why I chose to use the same approach for ProficientPython.com. The articles are interweaved with coding exercises, and each exercise is a mostly empty function definition with doctests. For example:

Screenshot of coding exercise for function called lesser_num, with doctests and no body

When a learner wants to check their work, they run the tests, and it will let them know if any tests have failed:

Screenshot of coding exercise for function called lesser_num, with doctests and an incorrect function body, plus test results that say 2 out of 3 tests passed

Each unit also includes a project, which is a Jupyter notebook with multiple function/class definitions. Some of the definitions already have doctests, like this project 2 function:

Screenshot of Jupyter notebook with a function definition with multiple tests

Sometimes, the learners must write their own doctests, like for this project 1 function:

Screenshot of Jupyter notebook cell with a function definition with a single test

When I'm giving those projects to a cohort of students, I will also look at their code and give them feedback, as the projects are the most likely place to spot bad practices. Even if a function passes all of its tests, that doesn't mean it's perfect: it may have performance inefficiencies, it may not cover all edge cases, or it just may not be fully "Pythonic".

There's a risk to this functions-based approach: learners have to wrap their minds around functional abstraction very early on, and that can be really tricky for people who are brand new to programming. I provide additional resources in the first unit, like videos of me working through similar exercises, to help those learners get over that hump.

Another drawback is that the functions-based approach doesn't feel quite as "fun" at first glance, especially for those of us who love drawing shapes on the screen and are used to creating K-12 coding courses. I tried to make the exercises interesting in the topics that they tackle, like calculating dog ages or telling fortunes. For the projects, many of them combine function definitions with side effects, such as displaying images, getting inputs from the user, and printing out messages.

Browser-based Python exercises

As programming teachers know, one of the hardest parts of teaching programming is the environment setup: getting every student machine configured with the right Python version, ensuring the right packages are installed, configuring the IDE with the correct extensions, etc. I think that it's both important for students to learn how to set up their personal programming environment, but also that it doesn't need to be a barrier when initially learning to program. Students can tackle that when they're already excited about programming and what it can do for them, not when they're dabbling and wondering if programming is the right path for them.

For ProficientPython.com, all of the coding can be completed in the browser, via either inline Pyodide-powered widgets for the exercises or Google CoLab notebooks for the projects.

Pyodide-powered coding widgets

Pyodide is a WASM port of Python that can run entirely in the browser, and it has enabled me to develop multiple free browser-based Python learning tools, like Recursion Visualizer and Faded Parsons Puzzles.

For this course, I developed a custom web element that anyone can install from npm: python-code-exercise-element. The element uses Lit, a lightweight framework that wraps the Web Components standards. Then it brings in CodeMirror, the best in-browser code editor, and configures it for Python use.

When the learner selects the "Run Code" or "Run Tests" button, the element spins up a web worker that brings in the Pyodide JS and runs the Python code in the worker. If the code takes too long (> 60 seconds), it assumes there's an infinite loop and gives up.

Screenshot of function definition with a while True loop and output that says the program took too long

If the code successfully finishes executing, the element shows the value of the final expression and any standard output that happened along the way:

For a test run, the element parses out the test results and makes them slightly prettier.

The element uses localStorage in the browser to store the user's latest code, and restores code from localStorage upon page load. That way, learners can remember their course progress without needing the overhead of user login and a backend database. I would be happy to add server-side persistence if there's demand, but I love that the course in its current form can be hosted entirely on GitHub Pages for free.

Online Jupyter notebooks

The projects are Jupyter notebooks. Learners can download and complete them in an IDE if they want, but they can also simply save a copy of my hosted Google CoLab notebook and complete them using the free CoLab quota. I recommend the CoLab option, since then it's easy for people to share their projects (via a publicly viewable link), and it's fun to see the unique approaches that people use in the projects.

I have also looked into the possibility of Pyodide-powered Jupyter notebooks. There are several options, like JupyterLite and Marino, but I haven't tried them out yet, since Google CoLab works so well. I'd be happy to offer that as an option if folks want it, however. Let me know in the issue tracker.

Why I made the course

I created the course content originally for Uplimit.com, a startup that initially specialized in public programming courses, and hosted the content in their fantastic interactive learning platform. I delivered that course multiple times to cohorts of learners (typically professionals who were upskilling or switching roles), along with my co-teacher Murtaza Ali who I first met in UC Berkeley CS61A.

We would give the course over a 4-week period, 1 week for each unit, starting off each week with a lecture to introduce the unit topics, offering a special topic lecture halfway through the week, and then ending the week with the project. We got great questions and feedback from the students, and I loved seeing their projects.

Once Uplimit pivoted to be an internal training platform, I decided it was time to share the content with the world, and make it as interactive as possible.

If you try out the course and have any feedback, please post in the discussion forum or issue tracker. Thank you! 🙏🏼

Sunday, June 1, 2025

Teaching Python with Codespaces

Whenever I am teaching Python workshops, tutorials, or classes, I love to use GitHub Codespaces. Any repository on GitHub can be opened inside a GitHub Codespace, which gives the student a full Python environment and a browser-based VS Code. Students spend less time setting up their environment and more time actually coding - the fun part! In this post, I'll walk through my tips for using Codespaces for teaching Python, particularly for classes about web apps, data science, or generative AI.

Getting started

You can start a GitHub Codespace from any repository. Navigate to the front page of the repository, then select "Code" > "Codespaces" > "Create codespace on main":

By default, the Codespace will build an environment based off a universal Docker image, which includes Python, NodeJS, Java, and other popular languages.

But what if you want more control over the environment?

Dev Containers

A dev container is an open specification for describing how a project should be opened in a development environment, and is supported by several IDEs, including GitHub Codespaces and VS Code (via Dev Containers extension).

To define a dev container for your repository, add a devcontainer.json that describes the desired Docker image, VS Code extensions, and project settings. Let's look at a few examples, from simple to complex.

A simple dev container configuration

The simplest devcontainer.json specifies a Docker image, like from Docker Hub or the Microsoft Artifact Registry. Microsoft provides several Python-specific images optimized for dev containers.

For example, my python-3.13-playground repository sets up Python 3.13 using one of those images, and also configures a few settings and default extensions:

{
  "name": "Python 3.13 playground",
  "image": "mcr.microsoft.com/devcontainers/python:3.13-bullseye",
  "customizations": {
    "vscode": {
      "settings": { 
        "python.defaultInterpreterPath": "/usr/local/bin/python",
        "python.linting.enabled": true
      },
      "extensions": [
        "ms-python.python",
        "ms-python.vscode-pylance",
        "ms-python.vscode-python-envs"
      ]
    }
  }
}

The settings inside the "vscode" field will be used whenever the playground is opened in either GitHub Codespaces or local VS Code.

A dev container with Dockerfile

We can also customize a dev container with a custom Dockerfile, if we want to run additional system commands on the image.

For example, the python-ai-agent-frameworks-demos repository uses a Dockerfile to install required Python packages:

FROM mcr.microsoft.com/devcontainers/python:3.12-bookworm

COPY requirements.txt /tmp/pip-tmp/

RUN pip3 --disable-pip-version-check install -r /tmp/pip-tmp/requirements.txt \
    && rm -rf /tmp/pip-tmp

The devcontainer.json references the Dockerfile in the "build" section:

{
  "name": "python-ai-agent-frameworks-demos",
  "build": {
    "dockerfile": "Dockerfile",
    "context": ".."
  },
  "customizations": {
    "vscode": {
      "extensions": [
        "ms-python.python",
        "ms-azuretools.vscode-bicep"
      ],
      "python.defaultInterpreterPath": "/usr/local/bin/python"
    }
  },
  "remoteUser": "vscode"
}

You can also install OS-level packages in the Dockerfile, using Linux commands like apt-get, as you can see in this fabric-mcp-server Dockerfile.

A devcontainer with docker-compose.yaml

When our dev container is defined with a Dockerfile or image name, the Codespace creates an environment based off a single Docker container, and that is the container that we write our code inside.

It's also possible to setup multiple containers within the Codespace environment, with a primary container for our code development, plus additional services running on other containers. This is a great way to bring in containerized services like PostgreSQL, Redis, MongoDB, etc - anything that can be put in a container and exposed over the container network.

To configure a multi-container environment, add a docker-compose.yaml to the .devcontainer folder. For example, this docker-compose.yaml from my postgresql-playground repository configures a Python container plus a PostgreSQL container:

version: "3"

services:
  app:
    build:
      context: ..
      dockerfile: .devcontainer/Dockerfile
      args:
        IMAGE: python:3.12
    volumes:
      - ..:/workspace:cached
    command: sleep infinity
    network_mode: service:db

  db:
    image: postgres:latest
    restart: unless-stopped
    volumes:
      - postgres-data:/var/lib/postgresql/data
    environment:
      POSTGRES_DB: postgres
      POSTGRES_USER: admin
      POSTGRES_PASSWORD: LocalPasswordOnly

volumes:
  postgres-data:

The devcontainer.json references that docker-compose.yaml file, and declares that the "service" container is the primary container for the environment:

{
  "name": "postgresql-playground",
  "dockerComposeFile": "docker-compose.yaml",
  "service": "app",
  "workspaceFolder": "/workspace",
...

Teaching Web Apps

Now let's look at topics you might be teaching in Python classes. One popular topic is web applications built with Python backends, using frameworks like Flask, Django, or FastAPI. A simple webapp can use the Python dev container from earlier, but if the webapp has a database, then you'll want to use the docker-compose setup with multiple containers.

Flask + DB

For example, my flask-db-quiz example configures a Flask backend with PostgreSQL database. The docker-compose.yaml is the same as the previous PostgreSQL example, and the devcontainer.json includes a few additional customizations:

{
  "name": "flask-db-quiz",
  "dockerComposeFile": "docker-compose.yaml",
  "service": "app",
  "workspaceFolder": "/workspace",
  "forwardPorts": [5000, 50505, 5432],
  "portsAttributes": {
    "50505": {"label": "Flask port", "onAutoForward": "notify"},
    "5432": {"label": "PostgreSQL port", "onAutoForward": "silent"}
  },
  "customizations": {
    "vscode": {
      "extensions": [
        "ms-python.python",
        "mtxr.sqltools",
        "mtxr.sqltools-driver-pg"
      ]
      "settings": {
        "sqltools.connections": [
          {
          "name": "Container database",
          "driver": "PostgreSQL",
          "previewLimit": 50,
          "server": "localhost",
          "port": 5432,
          "database": "app",
          "username": "app_user",
          "password": "app_password"
          }
        ],
      }
    }
  },
  "postCreateCommand": "python3 -m pip install -r requirements-dev.txt && pre-commit install",
  "remoteUser": "vscode"
}

The "portsAttributes" field in devcontainer.json tells Codespaces that we're exposing services at those parts, which makes them easy to find in the Ports tab in VS Code.

Screenshot of Ports tab in GitHub Codespaces

Once the app is running, I can click on the URL in the Ports tab and open it in a new window. I can even right-click to change the port visibility, so I can share the URL with classmates or teacher. The URL will only work as long as the Codespace and app are running, but this can be really helpful for quick sharing in class.

Another customization in that devcontainer.json is the addition of the SQLTools extension, for easy browsing of database data. The "sqltools.connection" field sets up everything needed to connect to the local database.

Screenshot of SQLTools extension for browsing a database table

Django + DB

We can use a very similar configuration for Django apps, as demonstrated in my django-quiz-app repository.

By default, Django's built-in security rules are stricter than Flask's, so you may see security errors when using a Django app from the forwarded port's URL, especially when submitting forms. That's because Codespace "local" URLs aren't truly local URLs, and they bake the port into the URL instead of using it as a true port. For example, for a Django app on port 8000, the forwarded URL could be:

https://supreme-space-orbit-64xpgrxxxcwx4-8000.app.github.dev/

To get everything working nicely in Codespaces, we need Django to treat the forwarded URL as a trusted origin. I made that adjustment in settings.py:

ALLOWED_HOSTS = []
CSRF_TRUSTED_ORIGINS = ["http://localhost:8000",]
if env.get_value("CODESPACE_NAME", default=None):
  CSRF_TRUSTED_ORIGINS.append(
   f"https://{env('CODESPACE_NAME')}-8000.{env('GITHUB_CODESPACES_PORT_FORWARDING_DOMAIN')}"
  )

I've run into this with other frameworks as well, so if you ever get a cross-site origin error when running web apps in Codespaces, a similar approach may help you resolve the error.

Teaching Generative AI

For the past two years, a lot of my teaching has been around generative AI models, like large language models and embedding models. Fortunately, there are two ways that we can use Codespaces with those models for free.

GitHub Models

My current favorite approach is to use GitHub Models, which are freely available models for anyone with a GitHub Account. The catch is that they're rate limited, so you can only send a certain number of requests and tokens per day to each model, but you can get a lot of learning done on that limited budget.

To use the models, we can point our favorite Python AI package at the GitHub Models endpoint, and pass in a GitHub Personal Access Token (PAT) as the API key. Fortunately, every Codespace exposes a GITHUB_TOKEN environment variable automatically, so we can just access that directly from the env.

For example, this code uses the OpenAI package to connect to GitHub Models:

import openai

client = openai.OpenAI(
  api_key=os.environ["GITHUB_TOKEN"],
  base_url="https://models.inference.ai.azure.com")

Alternatively, when you are trying out a GitHub Model from the marketplace, select "Use this Model" to get suggested Python code and open a Codespace with code examples.

Screenshot of GitHub Models playground with Use this Model button

For more examples with other frameworks, most from the Python + AI series, check out:


Ollama

My other favorite way to use free generative AI models is Ollama. Ollama is a tool that you can download onto any OS that makes it possible to interact with local language models, especially SLMs (small language models).

On my fairly underpowered Mac M1 laptop, I can run models with up to 8 billion parameters (corresponding to ~5 GB download size). The most powerful LLMs like OpenAI's GPT 4 series typically have a few hundred billion parameters, quite a bit more, but you can get surprisingly good results from smaller models. The Ollama tooling runs a model as efficiently as possible based on the hardware, so it will use a GPU if your machine has one, but otherwise will use various tricks to make the most of the CPU.

Screenshot of Ollama running in terminal

I put together an ollama-python playground repo that makes a Codespace with Ollama already downloaded. All of the configuration is done inside devcontainer.json:

{
  "name": "ollama-python-playground",
  "image": "mcr.microsoft.com/devcontainers/python:3.12-bullseye",
  "features": {
    "ghcr.io/prulloac/devcontainer-features/ollama:1": {}
  },
  "customizations": {
    "vscode": {
      "settings": {
        "python.defaultInterpreterPath": "/usr/local/bin/python"
      },
      "extensions": [
        "ms-python.python"
      ]
    }
  },
  "hostRequirements": {
    "memory": "16gb"
  },
  "remoteUser": "vscode"
}

I could have installed Ollama using a Dockerfile, but instead, inside the "features" section, I added a dev container feature that takes care of installing Ollama for me. Once the Codespace opens, I can immediately run "ollama pull phi3:mini" and start interacting with the model, and also use Python programs to interact with the locally exposed Ollama API endpoints.

You may run into issues running larger SLMs, however, due to the Codespace defaulting to a 4-core machine with only 16 GB of RAM. In that case, you can change the "hostRequirements" to "32gb" or even "64gb" and restart the Codespace. Unfortunately, that will use up your monthly free Codespace hours at double or quadruple the rate.

Generally, making requests to a local Ollama model will be slower than making to GitHub Models, because they're being processed by relatively underpowered machines that do not have GPUs. That's why I start with GitHub models these days, but support using Ollama as a backup, to have as many options possible.

Teaching Data Science

We can also use Codespaces when teaching data science, when class assignments are more likely to use Jupyter notebooks and scientific computing packages.

If you typically set up your data science environment using anacadonda instead of pip, you can use conda inside the Dockerfile, as demonstrated in my colleague's conda-devcontainer-demo:

FROM mcr.microsoft.com/devcontainers/miniconda:0-3

RUN conda install -n base -c conda-forge mamba
COPY environment.yml* .devcontainer/noop.txt /tmp/conda-tmp/
RUN if [ -f "/tmp/conda-tmp/environment.yml" ]; then umask 0002 \
    && /opt/conda/bin/mamba env create -f /tmp/conda-tmp/environment.yml; fi \
    && rm -rf /tmp/conda-tmp

The corresponding devcontainer.json points the Python interpreter path to that conda environment:

{
  "name": "conda-devcontainer-demo",
  "build": { 
    "context": "..",
    "dockerfile": "Dockerfile"
  },
  "postCreateCommand": "conda init",
  "customizations": {
    "vscode": {
      "settings": {
        "python.defaultInterpreterPath": "/opt/conda/envs/demo"
      },
      "extensions": [
        "ms-python.python",
        "ms-toolsai.jupyter",
      ]
    }
  }
}

That configuration includes a "postCreateCommand", which tells Codespace to run "conda init" once everything is loaded in the environment, inside the actual VS Code terminal. There are times when it makes sense to use the lifecycle commands like postCreateCommand instead of running a command in the Dockerfile, depending on what the command does.

The extensions above includes both the Python extension and the Jupyter extension, so that students can get started interacting with Jupyter notebooks immediately. Another helpful extension could be Data Wrangler which adds richer data browsing to Jupyter notebooks and can generate pandas code for you.

If you are working entirely in Jupyter notebooks, then you may want the full JupyterLab experience. In that case, it's actually possible to open a Codespace in JupyterLab instead of the browser-based VS Code.

Disabling GitHub Copilot

As a professional software developer, I'm a big fan of GitHub Copilot to aid my programming productivity. However, in classroom settings, especially in introductory programming courses, you may want to discourage the use of coding assistants like Copilot. Fortunately, you can configure a setting inside the devcontainer.json to disable it, either for all files or specifically for Python:

"github.copilot.enable": {
   "*": true,
   "python": false
}

You could also add that to a .vscode/settings.json so that it would take effect even if the student opened the repository in local VS Code, without using the dev container.

Some classrooms then install their own custom-made extensions that offer more of a TA-like coding assistant, which will help the student debug their code and think through the assignment, but not actually provide the code. Check out the research from CS50 at Harvard and CS61A at UC Berkeley.

Optimizing startup time

When you're first starting up a Codespace for a repository, you might be sitting there waiting for 5-10 minutes, as it builds the Docker image and loads in all the extensions. That's why I often ask students to start loading the Codespace at the very beginning of a lesson, so that it's ready by the time I'm done introducing the topics.

Alternatively, you can use pre-builds to speed up startup time, if you've got the budget for it. Follow the steps to configure a pre-build for the repository, and then Codespace will build the image whenever the repo changes and store it for you. Subsequent startup times will only be a couple minutes. Pre-builds use up free Codespace storage quota more quickly, so you may only want to enable them right before a lesson and disable after. Or, ask if your school can provide more Codespace storage budget.

For additional tips on managing Codespace quotas and getting the most out of the free quotas, read this post by my colleague Alfredo Deza.

Any downsides?

Codespaces is a great way to set up a fully featured environment complete with extensions and services you need in your class. However, there are some drawbacks to using Codespaces in a classroom setting:

  • Saving work: Students need to know how to use git to be able to fork, commit, and push changes. Often students don't know how to use git, or can get easily confused (like all of us!). If your students don't know git, then you might opt to have them download their changed code instead and save or submit it using other mechanisms. Some teachers also build VS Code extensions for submitting work.
  • Losing work: By default, Codespaces only stick around for 30 days, so only changes are lost after then. If a student forgets to save their work, they will lose it entirely. Once again, you may need to give students other approaches for saving their work more frequently.

Additional resources

If you're a teacher in a classroom, you can also take advantage of these programs: