Fixed #7596. Added Model.objects.bulk_create, and make use of it in several places. This provides a performance benefit when inserting multiple objects. THanks to Russ for the review, and Simon Meers for the MySQl implementation.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16739 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/utils/functional.py

@@ -275,4 +275,17 @@ class lazy_property(property):
             @wraps(fdel)
             def fdel(instance, name=fdel.__name__):
                 return getattr(instance, name)()
-        return property(fget, fset, fdel, doc)
+        return property(fget, fset, fdel, doc)
+
+def partition(predicate, values):
+    """
+    Splits the values into two sets, based on the return value of the function
+    (True/False). e.g.:
+
+        >>> partition(lambda: x > 3, range(5))
+        [1, 2, 3], [4]
+    """
+    results = ([], [])
+    for item in values:
+        results[predicate(item)].append(item)
+    return results