Fixed #23982 -- Added doc note on generating Python 2/3 cross-compatible migrations.

way into your constructor, and then returns those arguments exactly when

deconstruct() is called.

Supporting Python 2 and 3

-------------------------

In order to generate migrations that support both Python 2 and 3, all string

literals used in your models and fields (e.g. ``verbose_name``,

``related_name``, etc.), must be consistently either bytestrings or text

(unicode) strings in both Python 2 and 3 (rather than bytes in Python 2 and

text in Python 3, the default situation for unmarked string literals.)

Otherwise running :djadmin:`makemigrations` under Python 3 will generate

spurious new migrations to convert all these string attributes to text.

The easiest way to achieve this is to follow the advice in Django's

:doc:`Python 3 porting guide </topics/python3>` and make sure that all your

modules begin with ``from __future__ import unicode_literals``, so that all

unmarked string literals are always unicode, regardless of Python version. When

you add this to an app with existing migrations generated on Python 2, your

next run of :djadmin:`makemigrations` on Python 3 will likely generate many

changes as it converts all the bytestring attributes to text strings; this is

normal and should only happen once.

.. _upgrading-from-south:

Upgrading from South