PYTHON

Django and the Python 3.13 REPL

Your new Django project uses Python 3.13.

You’re really looking forward to using the new REPL… but python manage.py shell just shows the same old Python REPL.
What gives?

Well, Django’s management shell uses Python’s code module to launch a custom REPL, but the code module doesn’t (yet) use the new Python REPL.

So you’re out of luck… or are you?

How stable do you need your shell command to be?

The new Python REPL’s code lives in a _pyrepl package.
Surely there must be some way to launch the new REPL using that _pyrepl package!

First, note the _ before that package name.
It’s _pyrepl, not pyrepl.

Any solution that relies on this module may break in future Python releases.

So… should we give up on looking for a solution, if we can’t get a “stable” one?

I don’t think so.

My shell command doesn’t usually need to be stable in more than one version of Python at a time.
So I’m fine with a solution that attempts to use the new REPL and then falls back to the old REPL if it fails.

A working solution

So, let’s look at a working solution.

Stick this code in a management/commands/shell.py file within one of your Django apps:

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"""Python 3.13 REPL support using the unsupported _pyrepl module."""
from django.core.management.commands.shell import Command as BaseShellCommand


class Command(BaseShellCommand):
    shells = ["ipython", "bpython", "pyrepl", "python"]

    def pyrepl(self, options):
        from _pyrepl.main import interactive_console
        interactive_console()

How it works

Django’s shell command has made it very simple to add support for your favorite REPL of choice.

The code for the shell command loops through the shells list and attempts to run a method with that name on its own class.
If an ImportError is raised then it attempts the next command, stopping once no exception occurs.

Our new command will try to use IPython and bpython if they’re installed and then it will try the new Python 3.13 REPL followed by the old Python REPL.

If Python 3.14 breaks our import by moving the interactive_console function, then an ImportError will be raised, causing us to fall back to the old REPL after we upgrade to Python 3.14 one day.
If instead, the interactive_console function’s usage changes (maybe it will require arguments) then our shell command will completely break and we’ll need to manually fix it when we upgrade to Python 3.14.

What’s so great about the new REPL?

If you’re already using IPython or BPython as your REPL and you’re enjoying them, I would stick with them.

Third-party libraries move faster than Python itself and they’re often more feature-rich.
IPython has about 20 years worth of feature development and it has features that the built-in Python REPL will likely never have.

If you’re using the default Python REPL though, this new REPL is a huge upgrade.
I’ve been using it as my default REPL since May and I love it.
See my screencast on Python 3.13 for my favorite features in the new REPL.

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