From a1952c4a0a21b14887bd536fc494d15516667b37 Mon Sep 17 00:00:00 2001
From: Guido van Rossum <guido@python.org>
Date: Wed, 24 Aug 2016 13:33:22 -0700
Subject: [PATCH] Type should not inherit from type. (#267)

Fixes #266.
---
 python2/test_typing.py | 13 +++++++++++++
 python2/typing.py      |  2 +-
 src/test_typing.py     | 12 ++++++++++++
 src/typing.py          |  2 +-
 4 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/python2/test_typing.py b/python2/test_typing.py
index 6cff13c3..d72a5896 100644
--- a/python2/test_typing.py
+++ b/python2/test_typing.py
@@ -1159,6 +1159,19 @@ def new_user(user_class):
 
         joe = new_user(BasicUser)
 
+    def test_type_optional(self):
+        A = Optional[Type[BaseException]]
+
+        def foo(a):
+            # type: (A) -> Optional[BaseException]
+            if a is None:
+                return None
+            else:
+                return a()
+
+        assert isinstance(foo(KeyboardInterrupt), KeyboardInterrupt)
+        assert foo(None) is None
+
 
 class NewTypeTests(BaseTestCase):
 
diff --git a/python2/typing.py b/python2/typing.py
index 138521bd..03632eaf 100644
--- a/python2/typing.py
+++ b/python2/typing.py
@@ -1529,7 +1529,7 @@ def __new__(cls, *args, **kwds):
 
 
 # This is not a real generic class.  Don't use outside annotations.
-class Type(type, Generic[CT_co]):
+class Type(Generic[CT_co]):
     """A special construct usable to annotate class objects.
 
     For example, suppose we have the following classes::
diff --git a/src/test_typing.py b/src/test_typing.py
index 72afe670..1f5e72fe 100644
--- a/src/test_typing.py
+++ b/src/test_typing.py
@@ -1426,6 +1426,18 @@ def new_user(user_class: Type[U]) -> U:
 
         joe = new_user(BasicUser)
 
+    def test_type_optional(self):
+        A = Optional[Type[BaseException]]
+
+        def foo(a: A) -> Optional[BaseException]:
+            if a is None:
+                return None
+            else:
+                return a()
+
+        assert isinstance(foo(KeyboardInterrupt), KeyboardInterrupt)
+        assert foo(None) is None
+
 
 class NewTypeTests(BaseTestCase):
 
diff --git a/src/typing.py b/src/typing.py
index 5573a1fb..b628ba3d 100644
--- a/src/typing.py
+++ b/src/typing.py
@@ -1605,7 +1605,7 @@ def __new__(cls, *args, **kwds):
 
 
 # This is not a real generic class.  Don't use outside annotations.
-class Type(type, Generic[CT_co], extra=type):
+class Type(Generic[CT_co], extra=type):
     """A special construct usable to annotate class objects.
 
     For example, suppose we have the following classes::