Intermediate changes

1 files changed, 15 insertions, 4 deletions

diff --git a/contrib/python/zope.interface/py3/zope/interface/interface.py b/contrib/python/zope.interface/py3/zope/interface/interface.py
index 1bd6f9e818..8143daf3dd 100644
--- a/contrib/python/zope.interface/py3/zope/interface/interface.py
+++ b/contrib/python/zope.interface/py3/zope/interface/interface.py
@@ -15,14 +15,16 @@
 """
 # pylint:disable=protected-access
 import sys
-from types import MethodType
-from types import FunctionType
 import weakref
+from types import FunctionType
+from types import MethodType
+from typing import Union
 
+from zope.interface import ro
 from zope.interface._compat import _use_c_impl
 from zope.interface.exceptions import Invalid
 from zope.interface.ro import ro as calculate_ro
-from zope.interface import ro
+
 
 __all__ = [
     # Most of the public API from this module is directly exported
@@ -941,6 +943,14 @@ class InterfaceClass(_InterfaceClassBase):
     def __reduce__(self):
         return self.__name__
 
+    def __or__(self, other):
+        """Allow type hinting syntax: Interface | None."""
+        return Union[self, other]
+
+    def __ror__(self, other):
+        """Allow type hinting syntax: None | Interface."""
+        return Union[other, self]
+
 Interface = InterfaceClass("Interface", __module__='zope.interface')
 # Interface is the only member of its own SRO.
 Interface._calculate_sro = lambda: (Interface,)
@@ -1121,8 +1131,9 @@ def _wire():
 # pylint:disable=wrong-import-position
 from zope.interface.declarations import implementedBy
 from zope.interface.declarations import providedBy
-from zope.interface.exceptions import InvalidInterface
 from zope.interface.exceptions import BrokenImplementation
+from zope.interface.exceptions import InvalidInterface
+
 
 # This ensures that ``Interface`` winds up in the flattened()
 # list of the immutable declaration. It correctly overrides changed()