added random_queryset into QuerySet manager

docs/index.md

@@ -151,6 +151,10 @@ Reverses the order in which a queryset’s elements are returned.
 Returns a random object matched by the queryset, or `None`
 if there is no matching object.
 
+##### [](#header-5)random_queryset(maximum: int = None)
+
+Returns a random objects matched by the queryset.
+
 ##### [](#header-5)none()
 
 Returns instance of an `EmptyQuerySet`.
@@ -377,4 +381,4 @@ Case-insensitive ends-with.
 
 ##### [](#header-5)isnone
 
-Checks if the value is equal to Python `NoneType`.
+Checks if the value is equal to Python `NoneType`.

reobject/query/queryset.py

@@ -172,6 +172,13 @@ def random(self) -> Maybe['Model']:  # type: ignore
         else:
             return obj
 
+    def random_queryset(self, maximum: int = None) -> 'QuerySet':
+        _max = maximum or self.count()
+        return type(self)(
+            random.sample(self, _max),
+            model=self.model
+        )
+
     def reverse(self) -> 'QuerySet':
         return type(self)(
             reversed(self),
@@ -190,7 +197,7 @@ def values(self, *fields: Fields) -> 'QuerySet':
             model=self.model
         )
 
-    def values_list(self, *fields: Fields, flat: bool=False) -> 'QuerySet':
+    def values_list(self, *fields: Fields, flat: bool = False) -> 'QuerySet':
         # TODO: Allow order_by on values_list
 
         if not fields:

tests/unit/test_queryset.py

@@ -358,6 +358,14 @@ def test_manager_random(self):
 
         self.assertIn(obj, SomeModel.objects.all())
 
+    def test_manager_random_queryset(self):
+        SomeModel(p='foo', q=1)
+        SomeModel(p='bar', q=2)
+
+        objs = SomeModel.objects.random_queryset()
+        for obj in objs:
+            self.assertIn(obj, SomeModel.objects.all())
+
     def test_manager_map(self):
         SomeModel(p='foo', q=1)
         SomeModel(p='bar', q=2)
@@ -383,4 +391,4 @@ def test_manager_map_non_callable(self):
         SomeModel(p='bar', q=2)
 
         with self.assertRaises(TypeError):
-            result = SomeModel.objects.map(func=1)
+            result = SomeModel.objects.map(func=1)