From 6c0341f127c4d0772aff8e187e620fcb300fa9a9 Mon Sep 17 00:00:00 2001
From: Baptiste Mispelon <bmispelon@gmail.com>
Date: Fri, 29 Nov 2019 17:30:01 +0100
Subject: [PATCH] Refs #31046 -- Added
 django.db.models.utils.resolve_callables().

---
 django/db/models/query.py | 7 ++++---
 django/db/models/utils.py | 9 +++++++++
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/django/db/models/query.py b/django/db/models/query.py
index 08a6f421d1..73991df7bb 100644
--- a/django/db/models/query.py
+++ b/django/db/models/query.py
@@ -23,6 +23,7 @@ from django.db.models.fields import AutoField
 from django.db.models.functions import Cast, Trunc
 from django.db.models.query_utils import FilteredRelation, Q
 from django.db.models.sql.constants import CURSOR, GET_ITERATOR_CHUNK_SIZE
+from django.db.models.utils import resolve_callables
 from django.db.utils import NotSupportedError
 from django.utils import timezone
 from django.utils.functional import cached_property, partition
@@ -591,8 +592,8 @@ class QuerySet:
                 obj, created = self._create_object_from_params(kwargs, params, lock=True)
                 if created:
                     return obj, created
-            for k, v in defaults.items():
-                setattr(obj, k, v() if callable(v) else v)
+            for k, v in resolve_callables(defaults):
+                setattr(obj, k, v)
             obj.save(using=self.db)
         return obj, False
 
@@ -603,7 +604,7 @@ class QuerySet:
         """
         try:
             with transaction.atomic(using=self.db):
-                params = {k: v() if callable(v) else v for k, v in params.items()}
+                params = dict(resolve_callables(params))
                 obj = self.create(**params)
             return obj, True
         except IntegrityError as e:
diff --git a/django/db/models/utils.py b/django/db/models/utils.py
index b966029d63..989667dc8c 100644
--- a/django/db/models/utils.py
+++ b/django/db/models/utils.py
@@ -19,3 +19,12 @@ def make_model_tuple(model):
             "Invalid model reference '%s'. String model references "
             "must be of the form 'app_label.ModelName'." % model
         )
+
+
+def resolve_callables(mapping):
+    """
+    Generate key/value pairs for the given mapping where the values are
+    evaluated if they're callable.
+    """
+    for k, v in mapping.items():
+        yield k, v() if callable(v) else v