> ## Documentation Index
> Fetch the complete documentation index at: https://docs.codecrafters.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Python

> Learn how to solve CodeCrafters challenges in Python

<Note>
  **New to Python?** We recommend checking out [Automate the Boring Stuff with
  Python](https://automatetheboringstuff.com/) to get up to speed.
</Note>

## Local development

To run the code for your challenge locally, you'll need `python3` installed. Our test runners use version `3.12` (as of April 2024).

The script for your challenge (like `./spawn_redis_server.sh`) will run your code using this version of the Python interpreter. It looks something like this:

```sh theme={null}
#!/bin/sh

exec python3 -m app.main "$@"
```

## File structure

* The files for your solution are placed in the `app/` directory.
* `app/main.py` contains the `main` function, which is what the test runner executes.

## Adding more files

You can add more files and directories to `app/`. The test runner will include them when compiling your code.

For example, if you added a file at `app/foo.py`, you could use it like so:

<CodeGroup>
  ```Python app/main.py theme={null}

  from app.foo import foo

  def main():
      foo() // Uses the foo function from foo.py
  ```

  ```Python app/foo.py theme={null}
  def foo():
      print("Hello world!")
  ```
</CodeGroup>

## Adding dependencies

<Note>
  Not all challenges support managing dependencies via Pipenv at the moment.
  This will be fixed with the next Python version update.
</Note>

We use **Pipenv** for managing dependencies.

First install **Pipenv** using `pip`

```bash theme={null}
pip install pipenv
```

Now you can add dependencies to your project using `pipenv`

For example, to add the `requests` library, you can run the following command:

```bash theme={null}
pipenv install requests
```

This will create a virtual environment (if it doesn't exist) and add the following line to your `Pipfile`:

```toml theme={null}
[packages]
requests = "*"
```

It'll also make changes to your `Pipfile.lock`.