Fix dataclassses spelling (GH-28837) (GH-28841)

(cherry picked from commit 5b4a7675bcfc6368aff955f4a6231579718f5dad)

Co-authored-by: Landon Yarrington <33426811+jly36963@users.noreply.github.com>

Co-authored-by: Landon Yarrington <33426811+jly36963@users.noreply.github.com>
diff --git a/Doc/whatsnew/3.10.rst b/Doc/whatsnew/3.10.rst
index ddcefb4..5ac45c5 100644
--- a/Doc/whatsnew/3.10.rst
+++ b/Doc/whatsnew/3.10.rst
@@ -996,7 +996,7 @@
 Keyword-only fields
 ~~~~~~~~~~~~~~~~~~~
 
-dataclassses now supports fields that are keyword-only in the
+dataclasses now supports fields that are keyword-only in the
 generated __init__ method.  There are a number of ways of specifying
 keyword-only fields.
 
diff --git a/Lib/dataclasses.py b/Lib/dataclasses.py
index 7973997..aa84f1b 100644
--- a/Lib/dataclasses.py
+++ b/Lib/dataclasses.py
@@ -1387,7 +1387,7 @@ def exec_body_callback(ns):
         ns['__annotations__'] = annotations
 
     # We use `types.new_class()` instead of simply `type()` to allow dynamic creation
-    # of generic dataclassses.
+    # of generic dataclasses.
     cls = types.new_class(cls_name, bases, {}, exec_body_callback)
 
     # Apply the normal decorator.
diff --git a/Lib/test/test_dataclasses.py b/Lib/test/test_dataclasses.py
index a1d9112..bdcb4a2 100644
--- a/Lib/test/test_dataclasses.py
+++ b/Lib/test/test_dataclasses.py
@@ -1907,7 +1907,7 @@ class Parent(Generic[T]):
         # Check MRO resolution.
         self.assertEqual(Child.__mro__, (Child, Parent, Generic, object))
 
-    def test_dataclassses_pickleable(self):
+    def test_dataclasses_pickleable(self):
         global P, Q, R
         @dataclass
         class P: