Fixed #26638 -- Allowed callable arguments for...

        """

        try:

            with transaction.atomic(using=self.db):

                params = {k: v() if callable(v) else v for k, v in params.items()}

                obj = self.create(**params)

            return obj, True

        except IntegrityError:

according to this algorithm::

    params = {k: v for k, v in kwargs.items() if '__' not in k}

    params.update(defaults)

    params.update(({k: v() if callable(v) else v for k, v in defaults.items()})

    obj = self.model(**params)

    obj.save()

In English, that means start with any non-``'defaults'`` keyword argument that

doesn't contain a double underscore (which would indicate a non-exact lookup).

Then add the contents of ``defaults``, overriding any keys if necessary, and

use the result as the keyword arguments to the model class. As hinted at

above, this is a simplification of the algorithm that is used, but it contains

all the pertinent details. The internal implementation has some more

error-checking than this and handles some extra edge-conditions; if you're

interested, read the code.

use the result as the keyword arguments to the model class. If there are any

callables in ``defaults``, evaluate them. As hinted at above, this is a

simplification of the algorithm that is used, but it contains all the pertinent

details. The internal implementation has some more error-checking than this and

handles some extra edge-conditions; if you're interested, read the code.

If you have a field named ``defaults`` and want to use it as an exact lookup in

``get_or_create()``, just use ``'defaults__exact'``, like so::

  chapter because it isn't related to that book, but it can't create it either

  because ``title`` field should be unique.

.. versionchanged:: 1.11

    Added support for callable values in ``defaults``.

``update_or_create()``

~~~~~~~~~~~~~~~~~~~~~~

A convenience method for updating an object with the given ``kwargs``, creating

a new one if necessary. The ``defaults`` is a dictionary of (field, value)

pairs used to update the object.

pairs used to update the object. The values in ``defaults`` can be callables.

Returns a tuple of ``(object, created)``, where ``object`` is the created or

updated object and ``created`` is a boolean specifying whether a new object was

race-condition which can result in multiple rows being inserted simultaneously

if uniqueness is not enforced at the database level.

.. versionchanged:: 1.11

    Added support for callable values in ``defaults``.

``bulk_create()``

~~~~~~~~~~~~~~~~~

Models

~~~~~~

* ...

* Added support for callable values in the ``defaults`` argument of

  :meth:`QuerySet.update_or_create()

  <django.db.models.query.QuerySet.update_or_create>` and

  :meth:`~django.db.models.query.QuerySet.get_or_create`.

Requests and Responses

~~~~~~~~~~~~~~~~~~~~~~

        self.assertFalse(created)

        self.assertEqual(obj, obj2)

    def test_callable_defaults(self):

        """

        Callables in `defaults` are evaluated if the instance is created.

        """

        obj, created = Person.objects.get_or_create(

            first_name="George",

            defaults={"last_name": "Harrison", "birthday": lambda: date(1943, 2, 25)},

        )

        self.assertTrue(created)

        self.assertEqual(date(1943, 2, 25), obj.birthday)

    def test_callable_defaults_not_called(self):

        def raise_exception():

            raise AssertionError

        obj, created = Person.objects.get_or_create(

            first_name="John", last_name="Lennon",

            defaults={"birthday": lambda: raise_exception()},

        )

class GetOrCreateTestsWithManualPKs(TestCase):

        )

        self.assertFalse(created)

        self.assertEqual(obj.defaults, 'another testing')

    def test_update_callable_default(self):

        obj, created = Person.objects.update_or_create(

            first_name='George', last_name='Harrison',

            defaults={'birthday': lambda: date(1943, 2, 25)},

        )

        self.assertEqual(obj.birthday, date(1943, 2, 25))